Roman emperor Constantine the Great is the one many believe changed church worship from Saturday sabbath to Sunday with his 321 AD Edict of Milan. The biggest sticklers for this bit of history are usually Seventh Day Adventists who use it to claim they are the only ones who worship correctly by observing Saturday sabbath, since Constantine was a sun-worshiping pagan posing as a Christian and all other churches bow to Constantine’s pagan tradition with their Sunday worship.
I’ve never read the Edict of Milan, so I don’t know if Constantine made Sunday worship official or not. Here’s what I do know. God is the one who established sabbath as the seventh day of the week and has never changed that. What did change is that Christians eventually moved away from worshiping on the seventh day and neither the Lord nor his apostles had a problem with that according to the New Testament (NT). This change was made long before Constantine was even born and the NT bears witness to this.
Before I get to what the NT says, I would like to point out that early Christians from the 100s AD, like Justin Martyr and Ignatius of Antioch, stated that the first day of the week, Sunday, was the day believers gathered together to observe the Lord’s day–i.e. the day of the Lord Jesus’ resurrection (see Ignatius’ Letter to the Magnesians, ch. 9, and Justin Martyr’s First Apology ch. 67). Now, to the NT. Jesus prophesied in John 16:2 that his followers would eventually be kicked out of the synagogues, although he and his disciples customarily attended synagogue on the sabbath (Matthew 12:1-9; Luke 4:16).
This happened during the missionary journeys of Paul, who also regularly attended synagogue. Acts 19 is the very last time scripture mentions Paul entering a synagogue. It was at Ephesus. After he preached the gospel in their synagogue, Jewish opposition to the gospel became so intense that Paul “departed from them, and separated the disciples,” (Acts 19:9). In the next chapter, which was several months later, we find that “upon the first day of the week, when the disciples came together to break bread, Paul preached unto them” in Troas (Acts 20:7). So the tradition of believers meeting on Sunday, the first day of the week, had already begun.
In 1 Corinthians 16:2, Paul instructs the congregation to collect their offerings for the poor on the first day of the week, which implies that’s when they were all gathered together. The final reference to the “Lord’s day” is by John in Revelation. The Lord’s day is when Jesus gave him the Revelation (Rev. 1:10).
Taking into account what Paul witnessed in Acts, it’s no wonder he said to the Romans:
4 Who art thou that judgest another man’s servant? to his own master he standeth or falleth. Yea, he shall be holden up: for God is able to make him stand.
5 One man esteemeth one day above another: another esteemeth every day alike. Let every man be fully persuaded in his own mind.
6 He that regardeth the day, regardeth it unto the Lord; and he that regardeth not the day, to the Lord he doth not regard it. Romans 14
Additionally, he told the Colossians:
14 Blotting out the handwriting of ordinances that was against us, which was contrary to us, and took it out of the way, nailing it to his cross;
16 Let no man therefore judge you in meat, or in drink, or in respect of an holyday, or of the new moon, or of the sabbath days:
17 Which are a shadow of things to come; but the body is of Christ. Colossians 2
Therefore, we can conclude God is only concerned about us setting aside time to worship him, not what day that time occurs on.
Harry A. Gaylord