Most Christians gather for worship on Sunday, but many cannot explain why. Some have been told that Sunday is the Christian Sabbath. Others have heard that the Catholic Church or the Roman emperor Constantine changed the day of worship from Saturday to Sunday. We need to set those claims aside and see what the Bible says.

The Jewish Sabbath was the seventh day of the week, which is Saturday. God commanded Israel:

“Remember the sabbath day, to keep it holy” (Exodus 20:8).

God did not change the Sabbath from Saturday to Sunday. The Bible never calls Sunday the Sabbath. Sunday worship is not based on moving the Sabbath forward one day. It is based on the resurrection of Jesus Christ and the example given to us by the early church.

Jesus rose from the dead on the first day of the week.

“Now after the Sabbath, as it began to dawn toward the first day of the week, Mary Magdalene and the other Mary came to look at the grave” (Matthew 28:1).

Mark, Luke, and John also tell us that the women came to the tomb on the first day of the week and found it empty. Sunday became important to believers because it was the day Jesus defeated death and rose from the grave.

Later that same day, the disciples were gathered together behind closed doors. Jesus appeared among them.

“So when it was evening on that day, the first day of the week, and when the doors were shut where the disciples were, for fear of the Jews, Jesus came and stood in their midst and said to them, ‘Peace be with you’” (John 20:19).

The resurrection changed everything. The disciples were not honoring a pagan day or following a church tradition. They were rejoicing in the risen Savior.

After the church began, believers continued gathering on the first day of the week. Acts tells us:

“On the first day of the week, when we were gathered together to break bread, Paul began talking to them” (Acts 20:7).

This was a gathering of believers. They broke bread, and Paul taught them from the Word of God. This gives us a clear picture of the early church meeting on Sunday.

Paul also told the believers in Corinth:

“On the first day of every week each one of you is to put aside and save, as he may prosper” (1 Corinthians 16:2).

Paul expected the believers to set aside their giving on the first day of every week. This makes sense if that was the regular day when the church gathered.

John later wrote:

“I was in the Spirit on the Lord’s day” (Revelation 1:10).

John did not explain what the Lord’s Day was, probably because the believers already understood the term. Christians came to use it for the first day of the week, the day on which their Lord rose from the dead.

There is no biblical support for the claim that Constantine invented Sunday worship. Constantine lived in the fourth century. The book of Acts and Paul’s first letter to the Corinthians were written hundreds of years earlier. Christians were already gathering on the first day of the week while the apostles were still alive.

What, then, should Christians do with the Sabbath command?

The Sabbath was a sign of God’s covenant with Israel.

“So the sons of Israel shall observe the sabbath, to celebrate the sabbath throughout their generations as a perpetual covenant. It is a sign between Me and the sons of Israel forever” (Exodus 31:16–17).

The New Testament does not command the church to keep Israel’s Sabbath. Paul warned believers not to allow others to judge them over this matter:

“Therefore no one is to act as your judge in regard to food or drink or in respect to a festival or a new moon or a Sabbath day—things which are a mere shadow of what is to come; but the substance belongs to Christ” (Colossians 2:16–17).

The Sabbath pointed forward to something greater. Its fulfillment is found in Christ. We do not earn God’s favor by observing a certain day. Our salvation and rest are found in Jesus Christ.

Paul also wrote:

“One person regards one day above another, another regards every day alike. Each person must be fully convinced in his own mind” (Romans 14:5).

That verse would make little sense if Christians were required to keep a certain day as Israel kept the Sabbath. Believers were not to condemn one another over the observance of special days.

Sunday worship is not a command that makes Sunday holy in the same way the Sabbath was holy under the old covenant. It is the clear pattern left by the early church. Christians gather on the first day of the week because Jesus rose on that day, believers gathered on that day, the Word was taught on that day, the Lord’s Supper was observed, and offerings were collected.

This does not mean that Sunday is the only day when Christians can worship. We should worship God every day. Churches may gather on other days as well. The first believers sometimes met daily. Worship is not limited to one building or one day of the week.

However, believers do need to gather.

“Not forsaking our own assembling together, as is the habit of some, but encouraging one another” (Hebrews 10:25).

A Christian should not use freedom from the Sabbath law as an excuse to neglect the church. Gathering with other believers for prayer, teaching, fellowship, and the Lord’s Supper is an important part of following Christ.

We worship on Sunday because it is the day our Lord rose from the dead and because it was the regular practice of the early church. Sunday did not replace Saturday as the Sabbath. Constantine did not invent Sunday worship. The pattern began in the New Testament, long before Constantine was born.

Every Sunday points us back to the empty tomb. Jesus Christ is alive. That is why Christians gather on the first day of the week.