Sforno on Leviticus 20:3/ספורנו על ויקרא כ׳:ג׳

1ואני אתן את פני באיש ההוא, if he does not refrain from carrying out his evil intention and does not become a בעל תשובה, a repentant sinner. Otherwise, even his judicial execution will not expiate for his sin.

2והכרתי אותו, seeing he has already been executed, these words refer to G’d excising this man’s soul’s share in the hereafter.

3למען טמא את מקדשי, by removing My presence from Israel, resulting in the people deserving to be stoned. ולחלל את שם קדשי, therefore I will turn My face against him even though he did not actually engage in idolatry.