GEN486 This should be explained as follows: [Hashem said to Kayin,] “Why are you downcast? If you improve your deeds and return to Me, then you will raise up,” which means you will raise up your face [from being downcast], the same language as Job 11:15, “then you will raise up your face without blemish. (Another understanding of Rabbeinu Yonah’s meaning here is that “raise up your face” means “[be able to] show your face,” i.e., you will regain your self-respect (see Ibn Ezra on Bereishis, ad loc.). This can further be interpreted as an expression of forgiveness. (i.e. the word שאת is an expression of forgiveness: “If you improve, you will be forgiven.”  [The verse continues] “But if you do not improve, then sin crouches [in wait] at the entrance” – if you do not repent from your sin, that is not the only iniquity that will remain with you.  For the yetzer crouches by the entrance, ready to cause you to sin in all that you do – once it is victorious, it will continue to be so.  It will lay obstacles in your path and you will find yourself ensnared Jeremiah 50:24, bereft of repentance. “Its longing is towards you” – to lead you astray, and it lies in wait for you, at all times.  GATES 67