Rashi on Deuteronomy 13:9/רש"י על דברים י״ג:ט׳

1לא תאבה לו THOU SHALT NOT CONSENT UNTO HIM — i.e. thou shalt feel no longing (תאב) towards him, thou shalt show no affection for him (אהב); This is stated because it is said, (Leviticus 19:18) “Thou shalt love thy fellowman as thyself”; this man, however, thou shalt not love (Sifrei Devarim 89:1).

2ולא תשמע אליו AND THOU SHALT NOT HEARKEN UNTO HIM when he makes entreaty for his life, that you should forgive him. This is stated because it says. (Exodus 23:5) “[If thou see the ass of him that hateth thee] thou shalt surely help him”; this man, however, thou shalt not help (Sifrei Devarim 89:2).

3ולא תחוס עינך עליו NEITHER SHALL THINE EYE SPARE HIM — This is stated because it says, (Leviticus 19:16) “thou shalt not stand against the blood of thy fellow” — this man, however, thou shalt not spare (Sifrei Devarim 89:3).

4ולא תחמל NEITHER SHALT THOU PITY [HIM] — i.e. thou shalt not occupy thyself in his favour (you shall not seek to find anything favorable to him) (Sifrei Devarim 89:4).

5ולא תכסה עליו AND THOU SHALT NOT CONCEAL (COVER OVER) HIM — If you know anything about him that will condemn him, you are not allowed to keep silent (Sifrei Devarim 89:5).