Rav Tzadok (Takanas Hashavim 9) Through repentance willful transgressions are transformed into inadvertent errors or even merits; it constitutes a rectification of the past—specifically regarding actions already carried out—achieved by bringing one’s heartfelt repentance all the way to the root of the soul within the intellect reaching the Throne of Glory, from which the rectification of those past actions also emanates. The reason such acts are likened to inadvertent errors—specifically through repentance born of fear—is analogous to the case of one who intends to eat pork but ends up eating lamb: the Talmud likens this to an inadvertent error regarding forgiveness and atonement, because the person’s intent was to commit a forbidden act. Thus, even though the past is rectified—with everything transformed into merits, as all is the will of God and there is no evil at all "for You are with me"—nevertheless, if the original intent was to transgress, the act is still classified as an inadvertent error. Therefore it is necessary to rectify the intent until it is viewed entirely as a merit and not at all as a sin even though we know the original intent was to sin and do evil.
Rav Tzadok (Takanas Hashavim 9) The nature of Reish Lakish’s criminal past is not mentioned at all in the Talmud since it had already been repented and thus was no longer considered that he had sinned at all. It appears to me that the story that he sold himself to gladiators and killed all of them is also not regarded as sinful as Tosfos states there since this happened before he did teshuva, However it is not clear why this event was mentioned in the Talmud especially since it seems like he was going to be killed by the gladiators according to the customs of those times and thus it was tantamount to suicide. It is thus obvious to me that all his actions were done deliberatly for the sake of Heaven for the sake of repentance because there are views that suicide and self induced suffering is an appropriate way of teshuva..
Keser Rosh(132) An aveira Leshma has not been permitted at all from the time of the giving of the Torah otherwise why have the 613 Mitzvos
Nefesh HaChaim(01:21) And this was also the entire matter of the service of the Patriarchs, and all the early righteous ones who accomplished the Torah before it was given, as our rabbis commented on the verse: “from the ritually permitted animals…”. And they stated: “from here we conclude that Noach learned Torah”. And they stated:”Avraham upheld the entire Torah. It’s not that they were commanded and thus acting as they did from a legal perspective, for if it were so they would not have taken positions based on their own intellect and attainment, even if they had grasped that based on the context of the root of their soul- it would have been necessary to trespass and to change even a small part of one of all of God’s- commandments. Yaakov would not have married two sisters, nor would have Amram married his aunt.