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Yeshua said that!
Matthew 5:
[13] Ye are the salt of the earth: but if the salt have lost his savour, wherewith shall it be salted? it is thenceforth good for nothing, but to be cast out, and to be trodden under foot of men.
[14] Ye are the light of the world. A city that is set on an hill cannot be hid.
[15] Neither do men light a candle, and put it under a bushel, but on a candlestick; and it giveth light unto all that are in the house.
[16] Let your light so shine before men, that they may see your good works, and glorify your Father which is in heaven.
[17] Think not that I am come to destroy the law, or the prophets: I am not come to destroy, but to fulfil.
[18] For verily I say unto you, Till heaven and earth pass, one jot or one tittle shall in no wise pass from the law, till all be fulfilled.
[19] Whosoever therefore shall break one of these least commandments, and shall teach men so, he shall be called the least in the kingdom of heaven: but whosoever shall do and teach them, the same shall be called great in the kingdom of heaven.
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Don’t see “the Torah is sufficient of itself to be the final authority of Christian doctrine” in that prooftext. Of course that could well be your interpretation...