I’m an Italian Noahide.
With regard to the false prophet, this is what Rambam says:
Mishneh Torah-Yesodei haTorah 9:1
It is clear and explicit in the Torah that it is [God's] commandment, remaining forever without change, addition, or diminishment, as [Deuteronomy 13:1] states: "All these matters which I command to you, you shall be careful to perform. You may not add to it or diminish from it," and [Deuteronomy 29:28] states: "What is revealed is for us and our children forever, to carry out all the words of this Torah." This teaches that we are commanded to fulfill all the Torah's directives forever. It is also said: "It is an everlasting statute for all your generations," and [Deuteronomy 30:12] states: "It is not in the heavens." This teaches that a prophet can no longer add a new precept [to the Torah]. Therefore, if a person will arise, whether Jew or gentile, and perform a sign or wonder and say that God sent him to:
a) add a mitzvah, b) withdraw a mitzvah c) explain a mitzvah in a manner which differs from the tradition received from Moses, or d) if he says that the mitzvot commanded to the Jews are not forever, but rather were given for a limited time,
He is a false prophet. He comes to deny the prophecy of Moses and should be executed by strangulation, because he dared to make statements in God's name which God never made. God, blessed be His name, commanded Moses that this commandment is for us and our children forever, and, God is not man that He speak falsely
According to Rambam himself, not even the King Messiah appears authorized by HaShem, except my mistake, to modify the Torah:
Mishneh Torah-Melachim uMilchamot 11:3
One should not presume that the Messianic king must work miracles and wonders, bring about new phenomena in the world, resurrect the dead, or perform other similar deeds. This is definitely not true. (…) The main thrust of the matter is: This Torah, its statutes and its laws, are everlasting. We may not add to them or detract from them.
As is known to those who know Christian sacred texts, Yeshu would have argued that the divorce was a "concession" given by HaShem to the Israelites for the "hardness of their hearts”:
Gospel According to Matthew 19:1-8
And it came to pass when Jesus had finished these words, he departed from Galilee, and came into the borders of Judaea beyond the Jordan; and great multitudes followed him; and he healed them there. And there came unto him Pharisees, trying him, and saying, Is it lawful for a man to put away his wife for every cause? And he answered and said, Have ye not read, that he who made them from the beginning made them male and female, and said,For this cause shall a man leave his father and mother, and shall cleave to his wife; and the two shall become one flesh? So that they are no more two, but one flesh. What therefore God hath joined together, let not man put asunder. They say unto him,]Why then did Moses command to give a bill of divorcement, and to put her away? He saith unto them, Moses for your hardness of heart suffered you to put away your wives: but from the beginning it hath not been so.
Up to this point, in my opinion, there are no real problems of contrast between the affirmations of Yeshu and the Torah; in fact, beyond the somewhat questionable arguments of ha Notzri, it does not seem to me against the Law to invite anyone not to exercise a right recognized by the Law itself; the only hypothesis of contrast could perhaps be recognized, in my opinion of course, in the presence of full-blown adultery of the wife not punishable by the death penalty, a case in which, if I am not mistaken, the Oral Torah obliges the husband to repudiate his wife.
The problems arise for the second part of the teaching, where Yeshu would have pronounced extremely harsh sanctions against those who would instead use the right to divorce, as shown below:
"Anyone who divorces his wife, except in the case of fornication, exposes her to adultery,and whoever marries a divorced woman (except in the case of fornication) commits adultery."
"Anyone who divorces his wife, except in the case of fornication, and marries another commits adultery."
Gospel According to Mark 10:11
"Whoever divorces his wife and marries another, commits adultery against her."
Gospel according to Luke 16:18
"Whoever divorces his wife and marries another commits adultery; who marries a woman repudiated by her husband, commits adultery ".
The statements in Matthew 5:32 could perhaps, and I stress perhaps, be read as Yeshu's adherence to the teaching of Rabbi Shammai, which limited the lawfulness of divorce to cases of sexual impudence of the wife. However, all the other prescriptions of Yeshu reported above seem to me to objectively contest the precepts of the Torah, since they qualify with the very serious crime of adultery some perfectly legitimate conduct according to the Torah, which are:
Marry a divorced woman;
Divorce one's wife and marry another. This second "sanction" attributed to Yeshu also leads to an even more radical protest against the Torah, as in addition to contrasting with the institution of divorce it also distorts the case of adultery itself, which is the sexual intercourse between a man, no matter if married unless, and the wife of another, or with his arusah.Excepted my mistake, if a married Jewish man betrays his wife with an unmarried woman, he does not commit adultery, but possibly the less serious crime of prostitution ex Deuteronomy 23: 18
I therefore wonder: but on the halachic plane, do these teachings of Yeshu qualify him as a false prophet? It seems so to me.