Le Lévitique 26:40 Commentaire : Kli Yakar, Sforno, Or HaChaim & Rav Hirsch

And they will confess their sin, etc. The reason it says after the confession, I too will behave toward them with casualness, is because it states, in their treachery that they committed against Me. The letter bet [meaning “in”] in in their treachery [bema’alam] suggests that they continue to be treacherous, for it should have said, “They shall confess their sin and their treachery.” Rather, even though they confess and admit that this sin caused their troubles, nevertheless they continue to be treacherous, their impurity still within them. This is like the custom in our generation, where everyone admits that certain well-known sins cause all the hardships, yet they still do not repent from them, making their confession like one who immerses in a ritual bath while holding a reptile [which keeps them impure].
Some say that they will not attribute [their suffering] to their sin alone, as they might say that their sins are not sufficient to bring all these plagues upon them, and they will attribute it also to the sin of their fathers. Therefore it says, I too will behave toward them with casualness, and then they will accept [the punishment for] their sin and attribute it to their own sin. But this interpretation is contradicted by what Daniel said: Because of our sins and the iniquities of our fathers, etc. (Daniel 9:16).

והתודו את עונם, only some of them, as we know from Daniel and Ezra.

והתודו את עונם, "And they will confess their sins, etc." Earlier commentators have not explained these verses to our satisfaction; most of their commentaries are too far fetched to be taken seriously. One of the reasons is that there appears no reason why the Jewish people at that time should confess the sins of their ancestors. As soon as they confess their own sins they are no longer guilty of perpetuating the evil ways of their fathers (compare Berachot 7). Secondly, why did the Torah (verse 41) write: "also I will walk contrary unto them?" Why does the Torah mention a punishment after the people have already confessed their sins? Thirdly, why does the Torah speak about G'd bringing the Israelites into the land of their enemies when we have heard this already in verse 33? Fourthly, what is the meaning of the words או אז יכנע לבבם הערל, "or perhaps their uncircumcised heart will be humbled?" Nachmanides interprets the word "or" as alluding to the two possible causes of the eventual redemption. Either it would occur due to repentance on a nation-wide scale or it would occur because G'd's timetable had been exhausted and the Jews had experienced sufficient punishment during their long years in exile. I believe this is a very forced explanation..