Do you mean that Christians should have Saturday as the Sabbath, like the Seventh-day Adventists?
All follower of Yeshua keep the true Sabbath.
Churchians keep the Sun god’s day: Sunday.
All of the apostles and their flocks kept the sabbath. Sabbath worship was continuous until the mid 4th century.
The book of Acts soundly affirms the keeping of the Sabbath and the appointed times. Sunday worship is the result of mostly misunderstanding of Havdalah (the “first day of the week” gathering on what we call saturday evening.
God’s days begin at sundown, so Havdalah was a coming together on “the first day of the week.” That is what was what was called “coming together on the first day of the week” in every instance in the entire NT.
Seventh Day Adventists are correct to some extent on that, but have other issues WRT the divinity of Yeshua.
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