For the true disciples of Christ, the day of rest is the same as
it was in Genesis and will be in Revelation - the Sabbath which
begins sunset Friday and ends sunset Saturday. It was changed by
the 4th Century AD leaders of the now Catholic Church but never
authorized by Jesus who followed all of God's Commands - this being
the 4th Command. Remember, Jesus said He did not come to change the
Law or the Prophets - not even in the smallest way or mark:
Matthew 5:17Contemporary English Version (CEV)The Law of Moses
17 Don't suppose that I came to do away with the Law and the Prophets. I did not come to do away with them, but to give them their full meaning.
In fact, every day is a day to honor the Lord but He did sanctify one day per week to be a day of rest and reflection upon Him and His Creation - the weekly Sabbath as noted above. Those who worship on any other day are not adhering to the 4th Command:
Matthew 15:9Contemporary English Version (CEV)9 It is useless for you
to worship me,
when you teach rules
made up by humans.