I'm saying you can't logically cite the New Testament as evidence in this case while not allowing it when Sunday worship people cite the several passages in the New Testament which justify Sunday worship.
Actually I would never argue against a NT text saying "week day 1 is now the Sabbath" or "the 4th commandment is now changed to apply to week day 1 instead of the 7th day" or "week day 1 is the LORD's Day and the new Sabbath". OR "remember to keep holy week day 1 - six days shall you labor and do you all your work but the first day is the Sabbath of the Lord Thy God".
Or "we no longer observe the 7th day as the Sabbath - rather we gather for worship every week day 1 as our keeping Sabbath in the New Testament".
Do you have such a text?? (I know of none).
Because until then - we do have the NT text in Mark 7 saying not to edit/tweek/modify the Commandments of God via tradition.
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Suppose for example you had
"week day 1 is the Lord's Day"
and "we gather for worship every week-day-1"
I would think you had two texts that finally give some support for week-day-1 as a holy day. And to prove that it is not 'another Holy Day' but rather the NEW day for Sabbath you might want to add 'and of course week-day-1 is the Sabbath".
A perfect combination of 3 texts... for which you have not even one of them.
fortunately we DO have this -
Mark 7
7 Howbeit in vain do they worship me, teaching for doctrines the commandments of men.
8 For laying aside the Commandment of God, ye hold the tradition of men, as the washing of pots and cups: and many other such like things ye do.
9 And he said unto them, Full well ye reject the commandment of God, that ye may keep your own tradition.
10 For Moses said, Honour thy father and thy mother; and, Whoso curseth father or mother, let him die the death:
11 But ye say, If a man shall say to his father or mother, It is Corban, that is to say, a gift, by whatsoever thou mightest be profited by me; he shall be free.
12 And ye suffer him no more to do ought for his father or his mother;
13 Making the Word of God of none effect through your tradition, which ye have delivered: and many such like things do ye.
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Now the Jews of course would never have claimed that they had deleted or done away with the 5th commandment - simply because they had tweaked it (by implication) a tiny bit by adding their own rules about what is CORBAN.
We know you wouldn't argue your exact requested words, you're a lawyer...
It is left as "an exercise for the reader" to see if that resolves the problem you have in the text -- at all.
Bible avoidance of the details in that discussion is not the great solution to the problem you seem to have at first imagined it to be.
in Christ,
Bob