From ReformedWord
The Lord's Day is a Divinely instituted holiday; a day of rest from our labor; an opportunity for worship and service; and a fore-taste of Heaven; all on the first day of every week. In the Modern Epoch, the Jewish Sabbath has been moved from Saturday to Sunday, though in all other ways remains unchanged. We would expect no less, since it was initiated in the Creation Story and confirmed as the Fourth Commandment.
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From Sabbath to Lord's Day
The New Testament never says in so many words that the Lord's Day has been moved from Saturday to Sunday. Sometimes people make a great deal of that fact. But is it really important? There are a number of things, as a matter of fact, that we rightly take to be the practice of apostolic Christianity that are never, in so many words, taught to be so.
Transitions Not Commanded
- There is nowhere a command to replace circumcision with baptism. We hear that Christians were baptized and we gather from things that the apostles wrote that baptism has the same theological and religious significance as circumcision, but we are never told in so many words that baptism has replaced circumcision. We are told that Gentile Christians do not have to be circumcised but we are not told that they don't have to be because they were baptized. In fact, when the question of whether Gentiles must be circumcised is directly addressed by the Jerusalem synod in Acts 15, it is remarkable that the answer to that question is deduced from the OT Scriptures. There is no apostolic deliverance as we might have expected. They figured it out from biblical prophecy and the fact of the Holy Spirit's blessing the Gentile mission. Theirs is an entirely reasonable conclusion but it is striking that we are never taught per se in the New Testament that baptism replaced circumcision or, for that matter, that it is to be given to females as well as to males. We are shown this, but the point is never made explicitly.
- In the same way, there is no command in the New Testament to baptize children. The doctrine of baptism taught and the way of salvation shown to us in the New Testament is very clearly a continuation of that revealed in the covenant that God made with Abraham and Israel, that covenant which included the Lord's promise to be their God and the God of their children; households continue to be the object of God's saving grace; children continue to be nurtured as members of the church; baptism is said to have the same signification as circumcision and covenant infants had been circumcised for two thousand years; there is no commandment to change the ancient practice, that is, not to give to covenant children the rite of initiation into the church, but, fact is, there is no command to baptize the infant children of Christian parents. It is, we believe, the inescapable conclusion to which the biblical data drive us, but it is never said in so many words.
- Or, once more, there is no command to carry over the duties and ministries of the Old Testament priesthood into the new form of New Testament ministry. We see it being done but the transition is never spelled out in so many words. It represented a great change, after all, moving from a hereditary ministry to a popularly chosen one. But even so great a change is more assumed in the New Testament than described, still less commanded.
- One more example. In the fifth commandment, we are told that those children who honor their parents will enjoy a long life in the land the Lord their God is giving them. It is a reference, of course, to Canaan, the Promised Land, to which Israel was heading when the Ten Commandments were given to her at Sinai. In Ephesians 6:1-3 that same commandment is cited as being still in force with its promise. But the promise is now not a long life in the Promised Land but "that it may go well with you and that you may enjoy long life on the earth." The specifically ancient-epoch form of the commandment has been replaced with a form suitable to a largely Gentile church. The commandment is the same but its circumstantial features have been altered to fit the new context. Still, nothing is said about this, no explanation is offered; we simply see it being done. So the change from Saturday to Sunday is very much like other consequential changes in form from ancient epoch to new epoch: indications clear enough in the New Testament but no explicit explanation.
In view of all this, the fact that there is no explicit command to begin celebrating the Sabbath on Sunday rather than on Saturday does not necessarily mean very much. In fact, it may be said that the New Testament's way of describing and enforcing this change from Saturday to Sunday – radical as it was – is actually quite typical. Lots of fundamental changes are taught in the same non-direct and more subtle way. The subtlety does not make the transition less important; in fact, it requires us to ponder its nature and meaning. We are shown it rather than taught it; we are given indications of the reasons for it but these are not spelled out. We must work them out.
The change from Saturday to Sunday
- Well, the story begins at Easter. It is remarkable, in fact, that all four Gospel Accounts begin their account of the resurrection with the time reference "the first day of the week." We certainly would have expected that they would have said rather that Jesus rose from the dead "on the third day." Over and over again the Lord predicted that he would rise from the dead on the third day, but instead, we are told that he rose on the first day of the week. There is no particular reason provided for this in the narrative itself, though it becomes very significant as time passes. The resurrection of our Lord occurred on the first day of the week and the Bible reminds us of this over and over again.
- Pentecost - The Lord then gives emphatic and immediate attention to this first day of the week by his own action. He first meets with his disciples during and again on the evening of that first day of the week. The next time he meets with them, so far as we know, it was again on the first day of the week. These initial gatherings of the new form of the Christian church took place on Sunday. Then the Spirit fell upon the church as it was gathered on the first day of the week. That point is not made explicitly, but 50 days after Passover gives us a Sunday, a point that would not have been missed by those Christians present. In the ancient epoch, God's people kept the Saturday Sabbath after the example of God. He rested on the seventh day after working the first six. Well, so it is in the new epoch. Christians keep the Lord's Day after Christ's example. He made the first day of the week the day of Christian assembly, the day of the Word of God and the Spirit of God by his own example. He met with them on Sunday! Sunday was the day on which he rested from his work of redemption and it became the new Lord's Day.
- The evidence, such as it is, found in the remainder of the New Testament confirms this evidence and its significance. We read in Acts 20:7 that Paul met with the church in Troas on the first day of the week – the same phrase we met with in the Gospel narratives of the Lord's resurrection – for a service of preaching and communion. Indeed, he not only met with the church on Sunday, but he waited a week in order to do so. In 1 Corinthians 16:2 we learn by the by that in Corinth also the first day of the week was the specifically Christian day of the week. All of this is all the more significant in view of the fact that the Saturday Sabbath was fixed deep in Jewish bones, one of the most precious and fundamental parts of Jewish piety. For Jewish men – and all the apostles were Jewish men – to preside over a church in which Sunday became the day for worship is the surest indication both that a change had been made and that the reason for it was monumentally important. In fact, the change from Saturday to Sunday, in the historical context of first century Judaism, is one of the most powerful proofs there is of the historicity of the resurrection of Jesus Christ. It would have to be something that momentous to convince Jews to alter their ancient day of rest and worship.
- All of this is then confirmed in Revelation 1:10 where we read John introduce his vision by saying, "On the Lord's Day I was in the Spirit..." Now, it is true that the term is not there defined. It doesn't say, "On the Lord's Day, that is, the first day of the week…" However, when you seek to discover what day is meant, there is but one answer: the first day of the week. This is what early Christianity universally understood by "the Lord's Day." You know that it is widely thought that Revelation was the last book of the New Testament to be written. That cannot be said to be a proven fact, but there are strong arguments in support of that conclusion. Irenaeus in the second century, for example, says that it was written quite recently, during the reign of the emperor Domitian (that is, in the last decade of the first century, from A.D. 90 to 95). Irenaeus was familiar with Asia Minor, was a personal friend of Polycarp, one of the sub-apostolic fathers from Asia Minor, Polycarp, for example, and his testimony carries great weight. But if Revelation were written then, in say A.D. 95, it was written only a few years before the first Christian writings to follow the New Testament itself. In those writings, "Lord's Day" is very clearly identified with Sunday. The Christian Sunday is obviously what early Christians understood the term to mean.
Why the Change?
Remember, "Lord's Day," in the Old Testament is simply another term for, a synonym of "Sabbath." The Sabbath is called "the Lord's holy day" in Isaiah 58 where the Lord himself also refers to it as "my holy day"; it is called a Sabbath to the Lord in Exodus 20; in Leviticus 23 we have reference made to the Lord's Sabbaths. But that means that the Sabbath day is now being observed on Sunday, according to the early church's understanding of the term as used in Rev. 1:10. They all knew the Lord's Day to refer to the Christian celebration on Sunday.
In the early second century bishop Ignatius' letter to the Magnesians (a church some fifteen miles from Ephesus), he warns the church against judaizing errors. "For if we still go on observing Judaism, we admit we never received grace. The divine prophets themselves lived Christ Jesus' way. That is why they were persecuted. Then, he goes on: "Those…who lived by ancient practices arrived at a new hope. They ceased to keep the Sabbath and lived by the Lord's Day, on which our life as well as theirs shone forth…" [9:1] By the way, that contrast between Sabbath – meaning the Jewish 7th day of the week – and the Lord's Day – meaning the Christian Sunday – almost certainly explains why the term Sabbath is not used in the New Testament for the Sunday Lord's Day. It is not, that is, if we do not count Hebrews 4. Sabbath meant in common usage the Saturday Sabbath. "Lord's Day" was used precisely so as not to confuse the two days. In The Epistle of Barnabas, after discussing the 4th commandment, the author goes on to say, "we keep the eighth day for rejoicing, in the which also Jesus rose from the dead, and having been manifested ascended into the heavens." [15] The eighth day is, of course, the first day of the week. In Justin's Apology we read: "…on the day called Sunday there is a meeting in one place of those who live in cities or the country…" and there follows an account of the Christian Sunday service. Justin then goes on to say, "We all hold this common gathering on Sunday, since it is the first day, on which God transforming darkness and matter made the universe, and Jesus Christ our Saviour rose from the dead on the same day." So, in the Didache, the early Christian manual for disciples, when we read "On every Lord's Day – his special day – come together and break bread and give thanks…" we may safely assume that the Lord's Day referred to there is also Sunday.
- God's two great works are the works of creation and redemption. The first Sabbath celebrated the first – having been introduced in Eden before the fall – and the second Sabbath celebrated the second, Christ's resurrection on the first day of the week representing the completion of Christ's redeeming work. It is the explicit and repeated tie in the New Testament between Christ's resurrection on the first day of the week and the Lord's Day that confirms this understanding.
It is interesting, by the way, that in the second giving of the Ten Commandments, the version we read in Dt 5, the reason for keeping the Sabbath holy is not God's working six days in creation and resting the seventh, but his having redeemed his people from bondage in Egypt. Already in the Ten Commandments we have provision made for a weekly Sabbath day that is a celebration of redemption, not creation.
- If Creation is a great, great thing, redemption is even greater. Creation required of the triune God wisdom and great power. But redemption required the suffering and death of God the Son. If the Saturday Sabbath was a fit memorial to that first great work, it is certainly not difficult to understand that a Sunday Sabbath would be a fit memorial for the still greater, nobler work.
The change to Sunday must have been a surprise to those devout folk so long used to a Saturday Sabbath. On the other hand, the witnesses of Christ's resurrection would have instinctively and immediately understood the reason for the change. The greatest thing that had ever happened or would ever happen in human history had just occurred. If the Lord wanted to memorialize that in the weekly pattern of his church's life, well, that makes perfect sense. But, whatever the reason, and whatever the struggle for later Jewish Christians to accept the change, there can be no doubt that such a change did take place in apostolic Christianity.
As in other aspects of worship the transition was made over some time. Jewish Christians, even apostles, continued to worship in the temple in Jerusalem until it was destroyed, even as they met for worship with their Christian congregations. In the same way, the Saturday Sabbath didn't fall away immediately, but the fact that it was going to be replaced by Sunday was obvious and it was precisely this fact that created such a controversy about the Saturday Sabbath. The Jewish Christians were offended by the fact that Gentiles were streaming into the church and no longer observing circumcision or their ancient Saturday Sabbath day. In these two momentous ways the church was ceasing to be distinctively Jewish as it had been for 2000 years. That was a hard thing to swallow. But the fact that they struggled to swallow it, is some of the most convincing evidence of all that apostolic Christianity had introduced a Sunday Lord's Day, which is, biblical phraseology being what it is, the same thing as saying that apostolic Christianity introduced a Sunday Sabbath.
Abrogated or Altered?
The argument is made that the 4th commandment still binds us, but only in a lesser way – requiring, for example, only going to church on Sunday – or that it means, in the new epoch, resting in Christ's righteousness rather than our own. That is, the 4th commandment has become a kind of gospel commandment. Where does this idea come from: that the Sabbath has passed away, at least in some form and some way? Proponents of this distortion site three texts:
Romans 14:1-6
The word "Sabbath" does not appear here and may not even be in view. Most likely, Paul is speaking of here concerned Jewish ceremonial regulations. The issue here is not the principle of legalism that Paul combated in Galatians: with that Paul would not compromise. Rather what Paul refers to here is observance of Jewish ceremonies by Jewish Christians. In all likelihood, the Gentiles were getting put out with the Jews who wanted to observe Jewish feast days.
The relationship between Jewish and Gentile Christians is a major issue in Romans so it is not surprising that practical issues relating to that subject should surface in the ethical section of the letter. Indeed, this section that begins in Romans 14:1 concerning weak and strong Christians concludes with an explicit commandment for Jews and Gentiles alike to practice unity in the church (15:5-13).
The obligation to keep the Sabbath holy is not a ceremony but part of the Moral Law that God laid down for the life of all mankind. Much more would have to be said here to give us leave to conclude that Paul was abolishing one of the Ten Commandments! Given what he has already said, earlier in the letter, to the praise of God's law, we may presume one thing he never imagined was that anyone would have thought he was abrogating one of the Ten Commandments! He was reminding the strong Christians to bear with the consciences of the weak who still felt it necessary to observe the Jewish ceremonial days (the feast days, the new moons, and, perhaps, the Saturday Sabbath) and were offended when the Gentile Christians showed no interest in doing so and urging the Gentile Christians to be cheerful in bearing with the consciences of their Jewish brethren
Colossians 2:16-19
"S" Sabbath day is listed together with religious festivals and New Moons (i.e. Jewish ceremonial rituals). The Sabbath day in view is not the weekly Sabbath but the other ritual days of the Jewish liturgical calendar that were also called "Sabbaths." (e.g. Leviticus 23:32 calls the Day of Atonement a Sabbath and v24 the Feast of Trumpets, because they were, like the other feasts, a day of rest from work.) It is an argument about Jewish rituals and Jewish forms of piety being imposed upon the new church and it is in that context that the Apostle tells the Christians in Colosse not to let anyone judge them about their observance of any of these ritual sabbath days. In such a case, there would be nothing here about the weekly Sabbath.
It is quite possible, however, that the weekly Sabbath is also in view here. But, of course, the Sabbath as the Jews insisted on its celebration, that is, on Saturday, not Sunday. It is the Jewish Sabbath that is the issue, as the context makes absolutely clear: the Jewish Sabbath as the Jewish religious festivals and the Jews' New Moon celebrations. It is precisely the unwillingness of Jewish Christians in the apostolic era to let go of their religious culture that proved such a controversy in those early years. They did not seem to mind the celebration of Sunday, but they were unwilling to let go of Saturday and of the Sabbath as they had come to practice it as Jews.
We know from church history that Jewish Christians and even some Gentile Christians continued to celebrate the Saturday Sabbath even as they celebrated Sunday and that was allowed in the church until much later when the Council of Laodicea (A.D. 364) declared observing Saturday – even together with Sunday – as "Judaizing." [1] Once the Sunday Lord's Day was introduced, it became a pressing question as to what would happen to the Saturday Lord's Day. That it became a controversial question is unmistakable and entirely predictable.
But, the fact is, apart from Seventh Day Adventists, a few Seventh Day Baptists, and some groups of Messianic Jews, no one disputes that the Saturday Lord's Day was no longer a necessary observance for Christians – Jews or Gentiles – once the Sunday Lord's Day began to be observed. It was acceptable to observe it, but not necessary. That would never have been enough for some Jewish Christians, hence the controversies. In any case, in context, the statement of Paul in Colossians 2 furnishes no evidence that the church is not to observe the Lord's Day.
Indeed, with respect to both Romans 14 and Colossians 2, one absolutely fatal argument against the view that these statements amount to a nullification of the Lord's Day as a day of perpetual obligation for Christians is the fact that, taken that way, the statements would prove too much. Taken that way, there would be no distinction of days remaining, but we know there is such a thing as the Lord's Day, for it is mentioned in the New Testament! We cannot take Rom. 14 and Col. 2 to mean the end of the Lord's Day because the New Testament bears its own witness to the fact that there was such a thing as the Lord's Day in apostolic Christianity. John mentions it in Rev. 1:10.
Hebrews 4:1-11
The idea that this text has something to do with the abrogation of the weekly Sabbath day is now generally denied. In the past, some Reformed theologians (e.g. Johannes Cocceius) taught that Hebrews 4 taught that the Sabbath of the New Testament Christian was his rest in Christ for salvation. In largest part, the argument rested on the present tense in verse 3. The idea was that when you become a Christian you enter the rest which, later in v9, is called a Sabbath rest. So Christians, by believing in Christ, have entered the rest of the Sabbath. That was taken to mean that the Sabbath in the OT was a sign of the rest that Christians would enter by faith in Christ. Christ brought the rest of which the Sabbath was the sign. What was anticipation in the OT is fulfillment in the NT and the Sabbath is, therefore, one of those shadows of the ceremonial law that is now fulfilled in Christ.
- First, and foremost, the rest or Sabbath rest of which we read in Hebrews 4 is the rest of heaven which Christians have not yet entered while in this world. That is the issue throughout the letter to the Hebrews – who will finally get to heaven – and it is the issue here as well. That point is made clearly in v11 when the author urges upon his Christian readers perseverance in the faith so that they will not fail to enter the rest. That is, they have not entered it yet and will not unless they persevere. Elsewhere in the New Testament heaven is described as rest. For example, we read in Revelation 14:13 of those who die in the Lord, "they will rest from the labor, for their deeds will follow them."
- Second, the present tense in v. 3 is like other such statements in the New Testament that enunciate a principle of salvation that are in the present tense. It is like Acts 14:22 where we read, "We must go through many hardships to enter the kingdom of God…" Here we are talking about how we get into heaven, just as in Hebrews 4:3. It is in the present tense but it manifestly does not mean that they are already in heaven. They must endure trials to get there. And here, they must believe and continue to believe in order to get there. Israel failed to enter in God's rest – both the Promised Land and heaven itself – because she did not persevere in faith. We must not make the same mistake or we'll suffer the same horrific consequence.
- The word translated Sabbath rest in v. 9, which is not the ordinary word for Sabbath but is like it, occurs for the first time in this text so far as anyone knows. If the author of this letter coined the term he obviously is connecting the weekly Sabbath with the rest of heaven. It is true; the Sabbath is a sign of things to come, a weekly anticipation of heaven. The Sabbath does have eschatological significance, but it has that for us as well as it did for believers in the ancient epoch. As Hebrews makes a point of saying, our situation, spiritually considered, is the same as Israel's in the wilderness not different, and we must make a pilgrimage to the Promised Land just as she had to. "Therefore, since the promise of entering his rest still stands, let us be careful that none of you be found to have fallen short of it." [v. 1] The Sabbath points to a fulfillment that is future for us as it was future for Israel.
- That being so, there is no argument here for the doing away with the Sabbath day. Quite the contrary. The argument of Hebrews 4 is that the Sabbath, as a day for anticipating heaven, is as necessary and helpful for us as it was for the people of God in the ancient epoch.
All of that to make this simple point. None of the texts often alleged to teach that the OT Sabbath, the fourth commandment has been set aside, do in fact teach any such thing. Some are talking about something else entirely and others are addressing the pressing issue of apostolic Christianity, how to make the transition in apostolic Christianity from Jewish piety to a largely Gentile one. What the New Testament has to say about the Sabbath fits either into that issue or confirms the sanctity of the Lord's Day we were already taught in the OT.
Lord of the Sabbath
"The key to all Christ's teaching on the Sabbath…lies in His conception of the original design of that divine institution. This conception we find expressed with epigrammatic point and conciseness, in contrast to the pharisaic idea of the Sabbath, in words uttered by Jesus on the occasion when He was defending his disciples. "The Sabbath," said He, "was made for man, and not man for the Sabbath." In other words, his doctrine was this: The Sabbath was meant to be a boon to man, not a burden; it was not a day taken from man by God in an exacting spirit, but a day given by God in mercy to man – God's holiday to his subjects; all legislation enforcing its observance having for its end to ensure that all should really get the benefit of the boon – that no man should rob himself, and still less his fellow-creatures, of the gracious boon.
This difference between Christ's mode of regarding of the Sabbath and the pharisaic involves of necessity a corresponding difference in the spirit and the details of its observance. Take Christ's view, and your principle becomes: That is the best way of observing the Sabbath which is most conducive to man's physical and spiritual well-being – in other words, which is best for his body and for his soul; and in the light of this principle, you will keep the holy day in a spirit of intelligent joy and thankfulness to God the Creator for his gracious consideration towards his creatures. Take the pharisaic view, and your principle of observance becomes: He best keeps the Sabbath who goes greatest lengths in mere abstinence from anything that can be construed into labour, irrespective of the effect of this abstinence either on his own well-being or on that of others. In short, we land in the silly, senseless minuteness of a rabbinical legislation, which sees in such an act as that of the disciples plucking and rubbing the ears of corn, or that of the healed man who carried his bed home on his shoulders, or that of one who should walk a greater distance than two thousand cubits, or three fourths of a mile, on a Sabbath, a heinous offence against the fourth commandment and its author."- A.B. Bruce
Mark 2
...for plucking grain on the Sabbath in Mark 2 and, of course, he did it on a number of occasions with respect to healing the sick on the Lord's Day. The Pharisees regarded such things as work and so violations of the commandment. Jesus says they were wrong. Now that is something to ponder because, of course, plucking grain on the Sabbath as they were walking along can hardly be said to be a work of necessity. These were grown men. They could have anticipated their need for food and prepared a lunch ahead of time. They could have, for that matter, waited until the day was over to have their meal. It would not have cost them anything to do without that food but a little bit of discomfort. What is that compared to holiness? Indeed, we regularly accept that the way of holiness is often going to be hard on our appetites! What is more, in Exodus 16, if you remember, a point was made not to gather manna on the Sabbath. But, all of this notwithstanding, the Lord said very plainly that his disciples committed no sin in plucking grain on the Sabbath. In fact, there in Mark 2, as you remember, he reminded them of David's use of the temple bread for his hungry troops to show them that such an act was, in the nature of the case, no violation of God's law even by the standards of the Law of Moses. It was such a thing that God would approve. The law was not meant to keep people hungry. And what the disciples did was not work as manna-gathering was for Israel in the wilderness – their daily pursuit of food – and so it violated no provision of the law of God. And he himself committed no sin by healing the sick on the Sabbath day. This is an important observation, especially for those whose tendency is to understand Sabbath keeping in terms of rules about what may and may not be done: every time the Lord encounters the Pharisees' Sabbath casuistry, he repudiates it. There is a tendency in religiously-minded hearts to mistake the nature of obedience to God's law. We must be careful not to make that mistake.
Luke 13:10-17, 14:1-6
Very clearly the synagogue ruler regarded Jesus' healing as working and so a violation of the 4th commandment.
The Lord Jesus does not take issue with the obligation of Sabbath-keeping. He never calls into question the importance of keeping the Lord's Day and he does not here. On this point he had no quarrel with the scribes and Pharisees. He never said of the Sabbath what he said about the regulations touching clean and unclean foods in Mark 7:19 – declaring them obsolete and soon to be annulled. He never said about the Sabbath what he said in John 4:21-24, about the sacrificial worship of the temple in Jerusalem, that it was soon to disappear. What he said to the Pharisees about the Lord's Day was completely different. He never said it was coming to an end; that it had served its purpose and was needed no more. What he said was this: what you condemn as violations of the Sabbath are not, in fact, violations at all. The 4th commandment, rightly understood, does not forbid such things at all, indeed, it permits them, encourages them, even demands them. The Sabbath law is holy, just, and good, but the Pharisees' interpretation of it was not. That is what he rejected. And the Pharisees had gone wrong precisely because they had lost sight of the purpose and intent of the Lord's Day.
The Pharisees clearly set a trap for Jesus. They wanted him to violate the law and so condemn himself. The Lord, however, aware of their designs, set a trap of his own. The way he asked his question leaves them with no choice but to appear either lax in obeying the Sabbath law – by doing what by their own definition must be work on the Sabbath – or harsh and unsympathetic toward a person in need. Not knowing how to extricate themselves from the dilemma, they said nothing.
What to Do
We begin where the Bible does with the Sabbath day as a day of rest from work. We are not to do our daily work on the Lord's Day. This is the burden of the first mention of the Sabbath, in Genesis 2:2-3, where the seventh day was made holy for us because on it God rested from his work of creating the world. He worked six days and rested the seventh.
Second, the Sabbath is a day of worship. This is the second great emphasis of the Bible's instruction regarding the keeping of the Lord's Day holy. Here we find the reason why the Bible speaks of the Lord's Day as a Sabbath to the Lord your God. This is the idea of the original statement in Gen. 2:2-3. There we read that God sanctified the seventh day. To sanctify something means to set it apart for use in the worship of God. And that is exactly what we find in the rest of the Bible. In Leviticus 23:3 we read:
"There are six days when you may work, but the seventh day is a Sabbath of rest, a day of sacred assembly."
A sacred or holy assembly is an assembly for worship. We don't rest from work simply to take time off. We rest from work so as to be free to do something else, viz. worship God. Other days of worship – Day of Atonement, Passover, Booths, etc. – were also called "Sabbaths" because they were not only times of holiday from work but were times of worship, of the assembly of the people of God in the presence of God.
In Lev. 19:30 we have the same connection between the Lord's Day and the worship of God: "Observe my Sabbaths and have reverence for my sanctuary."
In the Law of Moses there were special offerings in the temple for the Sabbath day (cf. Num. 28:9-10; 1 Chron. 23:31; 2 Chron. 8:13). In Ezekiel's vision of the future in chapter 46 we read that it will be "on the Sabbaths and New Moons" that the people will worship in the presence of the Lord. Psalm 92 is identified by its title as a "Psalm for the Sabbath Day" and it is very clearly a psalm for the worship of God's people. Interestingly, it speaks of worship both morning and evening. In Isaiah 1 we read of the Lord's anger at his people precisely because they were giving him insincere and hypocritical worship on the Sabbath.
And typical of the Bible, we are given little anecdotes that confirm its teaching. Do you remember 2 Kings 4 and its account of the woman to whom Elisha promised a son? And do you remember how that son later got sick and the woman was desperate to take him to the prophet. "She called her husband and said, ‘Please send me one of the servants and a donkey so I can go to the man of God quickly and return.' ‘Why go to him today?' he asked. ‘It's not the New Moon or the Sabbath.'"
In other words, in those days, the pious in Israel went on the Sabbath day to hear the prophets preach. They spent their Lord's Day as Christians do: they went to church and heard the Word of God. And so it continued to be. Jesus would characteristically go to the synagogue on the Sabbath day. The early church worshiped on the Lord's Day, we saw the evidence for that in Acts. And in the materials of early Christianity we learn that it was on the Lord's Day, the Christian Sunday, that the church gathered for worship.