Musar על בבא קמא 99:23

This is to awaken the hearts of those who want to be seduced [by their evil inclination] into thinking that the L-rd, blessed be He, will not bring up in his judgments the minute deeds and will not exact an accounting for them. Rather the general principle is "whoever says the Holy One blessed be He overlooks things will have his life overlooked" (Bava Kama 50a). Likewise they said: "if the evil inclination says to you: 'sin and the Holy One, blessed be He, will forgive you' - do not listen to him" (Chagiga 16a).