“The Jewish Sabbath was Saturday. So why do Christians say the Sabbath is Sunday?”
Ed: God made the world in six days, and rested on the seventh (Genesis 1–2). Thus he designed the working week, which has been the predominant measure of time ever since.
In the Bible the seventh day of the week (which we know as Saturday) is called the Sabbath, a word which comes from the Hebrew word meaning ‘rest’. In the Law of Moses which God gave to the nation of Israel to regulate their national life, observance of the Sabbath was compulsory: ‘the seventh day is a Sabbath to the Lord your God. On it you shall not do any work, you, or your son, or your daughter, your male servant, or your female servant, or your livestock, or the sojourner who is within your gates. For in six days the Lord made heaven and earth, the sea, and all that is in them, and rested on the seventh day. Therefore the Lord blessed the Sabbath day and made it holy’ (Exodus 20:10–11).
Throughout history, human experience has confirmed that one day off in every seven is an eminently healthy lifestyle choice, and many people who aren’t at all religious appreciate its value. But it’s a matter of personal choice. Christians are not obliged to keep the Law of Moses (Galatians 3:23–25), and this includes the observance of the Sabbath (Romans 14:5).
Sunday is the first day of the week, and the Bible never refers to it as the Sabbath. However, it’s clear that Sunday was a special day for Christians right from the start. It was the day they habitually met together (1 Corinthians 16:2); it seems it was the day when they shared the Lord’s Supper (Acts 20:7); it’s probably a Sunday which the Apostle John calls ‘the Lord’s day’ (Revelation 1:10).
Why did the early believers choose Sunday rather than Saturday as their special day? The answer is we don’t know. One reason may be that they were busy on the Sabbaths preaching to Jews in the synagogues (for example Acts 13:14 & 42, 17:2), so chose to set aside another day to meet together. And Sunday would be the obvious choice, because it was Sunday when the Lord Jesus Christ rose from the dead (John 20:1), and so it’s entirely fitting that this should be the day they chose to celebrate their faith in their risen Saviour.
There is no rule for followers of Christ which governs when they must meet. They can share fellowship and worship with each other and share the Lord’s supper as often as they wish. But the experience of generations has confirmed the wisdom of those first disciples, who made the Lord’s day the focus of their weekly routine.