What if you break a Noahide Law and don’t repent?

Here is some information about this from the book The Divine Code, 3rd Edition:

“Any Gentile who recognizes the existence of the One True G-d, and accepts upon himself the yoke of the G-d’s Kingship and the responsibility to keep the Seven Noahide Commandments from the Torah of Moses, will merit to be resurrected to receive a portion in the future World to Come. This person has elevated himself to become a Pious Gentile (a Hassid).

Many people are not familiar with the actual meaning of “the World to Come.” Some may be confusing it with the spiritual afterlife that is presently accessible to souls after physical death. The “World to Come” literally means the everlasting future era of the Resurrection, when G-dliness will be openly revealed in the physical creation. The World to Come will begin at some time after the start of the Messianic Era, which will be ushered in by Moshiach (the Messiah, who will be a Torah-observant Jewish leader who is descended father-to-son from Kings David and Solomon). In the World to Come, all death and spiritual negativity will be removed. Whereas now the physicality of this world hides G-dliness from the creations, in the World to Come, G-dliness will be revealed through the physical creation. Then the physical world will be the highest state of spiritual existence, higher than all the spiritual heavenly realms that presently exist.

If a faithful practicing Noahide commits an isolated transgression, for example due to weakness in the face of a severe temptation, it does not mean that all is lost. If the Noahide remains committed to the faith and observance of the Noahide Code, he/she can remove the sin by repentance. (This is the inner meaning of the Covenant of the Rainbow.) It may be necessary for a punishment of some sort to be Divinely decreed in order to complete the needed atonement for the soul, but the soul can still keep its share in the future World to Come.

Until the future “World to Come” will be established by G-d in the physical world and the Resurrection will occur, a person’s soul enters the spiritual realms after the death of the body. But a soul that does not secure a place in the future World to Come will at some point before then cease to exist, after it receives its due spiritual reward for any good deeds that were done.

A Gentile is judged by G-d according to the majority of his actions and ways, and if his good deeds outweigh his unrepented sins, he will merit a reward for his soul in the Heavenly realm after his passing. [Even if a person’s unrepented sins outweigh his good deeds, G-d will always grant the person a reward for his good deeds, either during his lifetime or after his passing.]

The weighing of a person’s deeds, to decide what is the majority for the person’s judgment, is done by G-d alone.[1]

If a Gentile’s good deeds and unrepented sins are exactly balanced, then his soul will be saved from Gehinom [the name for purgatory], but not because he is found righteous in judgment. Rather, G-d will tilt a balanced judgment toward kindness.

[However, that only applies to one who does not have the sin of forbidden relations included in his judgment of being half sinful. If unrepented forbidden relations are part of a Gentile’s judgment of being half sinful, his soul is assigned to Gehinom for twelve months of purification, and afterwards it will have a correction [2] (to then receive a reward in the Heavenly realm for the good deeds that the person did). This is a stringency regarding Divine judgment of the sin of forbidden relations for a Gentile, more than the judgment for deliberate violations of the commandments prohibiting theft or eating meat that was severed from a living animal. But the prohibitions of idol worship, blaspheming G-d’s Explicit Name [in Hebrew], and murder are the most severe of all, in that one who did not repent from deliberately committing any of these three sins has no reward at all for his soul in the Heavenly realm.]

The liability to Divine punishment refers to one who did not repent from his sin as required. One who did the correct repentance is forgiven by G-d, as explained in the following web pages (and in The Divine Code, Part I, Chapter 9):

Prayers for Repentance

Moral Conduct, and Repentance

Note 1: From Part I, footnote 29: Rambam writes in Laws of Kings 10:1 that a Gentile is liable for transgressing the Noahide Commandments due to negligence, since he should have learned them. But it seems that [Rambam] is only referring to a situation in which the general community knows the laws, yet this person excluded himself and didn’t learn them. If most of the members of the community don’t know the laws, one of these individuals is not liable unless he was … warned, since it was impossible for him to learn in his situation. Since the laws of G-d are true and just, such a person would not be liable under these unavoidable circumstances. It is clear that this only applies to the Noahide commandments that need to be taught (since they are not dictated by logic), such as details of the prohibitions against worshiping idols.

Note 2: There is not an explicit reference to reincarnation in the Tanakh (Hebrew Bible). But the holy writings of Talmud, Midrash, Kabbalah and Chassidus all have many discussions about the fact of reincarnation of souls, including discussions of the reincarnations of individuals and groups throughout history.