Why do Christians worship on Sunday, when in the Ten Commandments it clearly says to remember the Sabbath day and to keep it holy?
So we see that the tradition of the modern church of keeping the first day aside for worship originated from the early church and was overseen by the apostles themselves. Hence there is nothing incorrect to this.
What could be the motivation for this? My speculation is that many factors might have played a role in the adoption of this change. One of the reasons could be that the church believed that Jesus rose from the dead on a Sunday. Another could be that the church wanted to portray Christianity as different from Judaism. Yet another would be the convenience of worshiping on a Sunday as it was a holiday in the Roman empire.
As decades and centuries went by and most Christians came to be gentiles, Non-Jews, they dropped the Jewish sabbath and kept only the Christian gathering on Sunday. Some of them, but not all, also moved some Jewish sabbath customs to the new Christian holiday.
The Jewish sabbath customs are part of the Jewish law, Torah. The Torah is not binding on those who are not Jews, so Christians are not supposed to follow them. In the Ten Commandments, "remember the Sabbath day" is the only commandment that concerns Jewish ritual customs, so Christians applied "keeping it holy" to their own holiday.
The Jewishday runs from sunset to sunset, but the Roman day runs from midnight. So rising at the start of the day following the Sabbath to the Roman mind means Sunday.
There are still many Christians who observe the 7th-day Sabbath... and a few observe both days!
(tl:dr?) A long article which discusses this very complicated issue:
Biblical Sabbath
Colossians 2:16-17
16 Let no one, then, judge you in eating or in drinking, or in respect of a feast, or of a new moon, or of sabbaths,17 which are a shadow of the coming things, and the body [is] of the Christ;
Others have brought up that the Scriptures saw that the believers met on the first day of the week.
In more detail, the Sabbath was celebrated to keep it holy in rememberance of God's rest, or the finished work of creation. The Old Testament as a whole, according to Christian theology (see the Epistle to the Hebrews) foreshadows and points to Christ and the New Covenant. The Sabbath is fulfilled. How, do you ask?
When Jesus died and resurrected 3 days later it was on the first day of the week that he rose. Christians have sometimes called this the "8th day" because it marks the new creation. Through baptism we are made new creatures in Christ Jesus. This present, old age is passing away and the present age has come in Christ and his Church and will come in its fullness when he returns. We no longer celebrate the old creation, but the new creation.
Sabbath is also a typology for Christ. Jesus said "come unto me all ye weary and heavy laden and I will give you rest." Christ is our new Sabbath. We no longer rest on a day, but in a person. It is a perpetual Sabbath in which the works of the Law are no longer required of us. Christ is our Sabbath and we remember it on the day of his resurrection.
