Why do Christians assemble for worship every Sunday, the first day of the week? The bottom line answer is that Jesus arose on Sunday morning (Matthew 28:1-10; Mark 16:1-8; Luke 24:1, 13, 21, 46; John 20:1-19). Jesus’ resurrection makes the first day of the week, special, and that connection was so important that Christians began to call Sunday “the Lord’s Day” (Revelation 1:10).
The church likely began on a Sunday. The outpouring of the Holy Spirit, the first gospel sermon, and the baptism of 3000 occurred on the day of Pentecost (Acts 2:1). Pentecost (also known as the Feast of Weeks and the Feast of Harvest) was on the 50th day after the offering of the barley sheaf at the Feast of Unleavened Bread (Leviticus 23:15-21). The method used by the Sadducees for calculating the day of Pentecost always placed it on a Sunday.
The Lord’s Day assembly is not a matter of a command as was the Sabbath in the Ten Commandments. But we derive our authority not just from commands, but also from principles and apostolic precedents. Although the New Testament does command the assembly (Hebrews 10:25), the indication of the day of the week is given by example.
On the first day of the week, when we were gathered together to break bread, Paul talked with them, intending to depart on the next day, and he prolonged his speech until midnight. (Acts 20:7, ESV)
On the first day of every week, each of you is to put something aside and store it up, as he may prosper, so that there will be no collecting when I come. (1 Corinthians 16:2, ESV)
When we look at the writings of Christians in the second century, the worship assembly on every first day of week is clearly indicated. Justin Martyr illustrates this, “But Sunday is the day on which we all hold our common assembly, because it is the first day on which God, having wrought a change in the darkness and matter, made the world; and Jesus Christ our Saviour on the same day rose from the dead” (Apology, 67). Although the second century authors are not our authority, they help confirm the fact that we have rightly understood the apostolic example.
Jesus died for my sins, and death could not hold him captive. He is risen. I know of no greater thoughts. It is in our weekly assembly that we remember His death and proclaim His death for our sins until He comes again.