First, understand that I used quotation marks here because “THE LORD” was inserted into the scriptures to obscure the Creator’s name. His name is not “THE LORD.” His name is Yahweh, or Yah. There is nowhere in the entirety of scripture that Yah or His people ever call the first day of the week (SUNday) “the Lord’s day.”
There is nowhere in the entirety of scripture that even hints that Messiah’s resurrection altered the weekly Sabbath. The Sabbath on which Messiah rose again was the Feast of Firstfruits—the first day of the barley harvest (not a day of rest and holy convocation).
The only way to claim that scripture teaches the New Testament believers assembled as the ekklesia on the first day of the week, instead of on the Sabbath, is to pervert and distort the context of what we are told in scripture. Not once does scripture state such a thing. So, calling SUNday “the Lord’s day” simply reveals WHO one reveres as “lord.” According to the Father Himself, that would not be Him (and, ultimately, there is only one other choice).
The Sabbaths are given only to Yah’s family, they are not given to christianity, or any other religion. Those who have received His covenant, and have been told directly and personally by the Holy Spirit that they are Yah’s children, are the ones to whom He gives His Sabbaths (weekly and feast days) as a family sign.
The notion that SUNday is the “Lord’s day” is totally false teaching, and is a rejection of the Father and His family’s traditions. And, if one rejects the Father, one rejects the Son.
Understanding that is key in understanding how christianity is a counterfeit of the true faith.
For more information: Saturday or Sunday? Does It Even Matter?