The Daily Ma’amar of our Rebbe Rav Eliezer Berland shlit”a, courtesy of the “Hashem Hu HaElokim” leaflet:
The “Megaleh Amukot” (Ofen 241) explains about King Shaul, that Shaul knew that he was a reincarnation of Lemech, the sixth generation from Kayin, and Lemech avenged him [Kayin] when Tuval Kayin told him to shoot at an animal which had a horn in its forehead [Kayin, whom he mistook for an animal], and it was fulfilled in him the verse “If Kayin suffered vengeance after seven [generations].” And when Tuval Kayin and Lemech went to look into the condition of the animal with the horn, they saw that this was their beloved ancestor, and then Lemech clapped with his hands with terrible grief, and Tuval Kayin, who was a child and was standing between his two hands, was squashed and crushed to death. And Adah and Tzilah, who were truly righteous, immediately separated from Lemech, because they did not want to live with a murderer, especially since he murdered their ancestor and son.
And Lemech summoned them to a lawsuit in Rabbinical court before Adam HaRishon, and Adam HaRishon ruled that they must listen to Lemech, and then Adah and Tzilah said to Adam HaRishon: “And what about you? Why have you separated from your precious wife Chava these 130 years?!” And then Adam HaRishon understood his grave error and returned to his wife, and he fathered Shet — the soul of MoSheH, the initial letters of Moshe Shet Hevel.
For Shet was a reincarnation of Hevel, and afterwards he was reincarnated in Moshe who included all the souls of Israel, as it says “The people who are at your feet,” because they include the souls of the mixed multitude who are called “black” and the souls of the completely righteous who are called “comely,” that they are sanctified with the holiness of the Holy of Holies.
And therefore it is said, “Do not look upon me that I am swarthy because the sun has gazed upon me” — because the evil of all the evildoers is the outer aspect “because the sun has gazed upon me” — and not the inner aspect. Because the “sun” is the secret of choice, because the sun does not want to shine after it sees all the willful sinners of the world, and especially of the Jewish people, and it ascends to the celestial abode (zevul) — “The sun and the moon stood still in their abodes, [Israel] would travel by the light of Your arrows, by the lightning flash of Your spear” (Chabakuk 3:11), and the sun and the moon do not move until Hashem shoots into them arrows and spears, and so it is, every single day anew.
For the Kadosh Baruch Hu does not bring a downfall to the hands of the true Tzaddikim, because transgression brings about transgression, and beforehand a person sins unintentionally, and the unintentional brings about the intentional, and if a person does not immediately drive away the spirit of impurity from himself, as it says (Tehilim 119:67): “Before I was afflicted, I erred,” because in the beginning I was unintentional, like Lot who felt [only] in the end because it was unintentional, but he did not attempt to drive out the spirit of impurity from himself, and so he stumbled a second time; but the true Tzaddik, who is an aspect of Moshe, will never sin, not accidently, and all the more so not intentionally.