Answer
Observing a Sabbath day of rest/non-work was a command in the Old Covenant law (Exodus 20:8; 31:12–18). Christians are not under the law but have traditionally set aside Sunday as a day of worship and rest in remembrance of the fact that Jesus was resurrected on a Sunday. Some view Sunday as the Christian Sabbath, essentially transferring the Old Covenant laws about not working from sundown Friday to sundown Saturday to Sundays. Even in an increasingly secular culture, many businesses are still closed on Sundays. Is this biblical?
It is important to understand that the New Covenant nowhere commands worship or restricts work on Sundays. Biblically speaking, Sunday is not the Christian Sabbath. The New Testament describes Christians worshiping on Sundays (Acts 20:7; 1 Corinthians 16:2), but this is descriptive rather than prescriptive. Christians are described as worshiping on Sundays, but Sunday worship is nowhere prescribed or commanded. Nowhere in the New Testament are Christians even described as setting aside Sunday as a Sabbath day.
The Sabbath day was an important aspect of the covenant between God and Israel. Exodus 31:17 states, “It [the Sabbath day] is a sign forever between me and the people of Israel that in six days the LORD made heaven and earth, and on the seventh day he rested and was refreshed.” Prior to God giving the nation of Israel the Mosaic Law, God nowhere required Sabbath observance. After Jesus’ death on the cross perfectly fulfilled the Law, God nowhere requires Sabbath observance. Biblically speaking, Christians are not commanded to observe a Sabbath day on Saturday or Sunday or any other day of the week.
At the same time, following the creation pattern of six days of work followed by a day of rest is a good thing. Further, setting aside a day of the week to focus on worship is undeniably biblical (Hebrews 10:25), although we are to worship God every day, not just one day per week. And, ultimately, Jesus is our Sabbath rest (Hebrews 4).
In conclusion, no, Sunday is not the Christian Sabbath. There is no biblically commanded Christian Sabbath. But it is perfectly acceptable to set aside Sunday as a day for worship in light of Christ’s resurrection occurring on a Sunday. Also, making Sunday a day of rest to coincide with its being a day of worship seems a logical and, more importantly, biblically sound thing to do.