Whether hatred of one's neighbor is always a sin?

❌ Objection 1 : It would seem that hatred of one's neighbor is not always a sin. For no sin is commanded or counselled by God, according to Prov. 8:8: "All My words are just, there is nothing wicked nor perverse in them." Now, it is written (Lk. 14:26): "If any man come to Me, and hate not his father and mother . . . he cannot be My disciple." Therefore hatred of one's neighbor is not always a sin.

❌ Objection 2 : Further, nothing wherein we imitate God can be a sin. But it is in imitation of God that we hate certain people: for it is written (Rm. 1:30): "Detractors, hateful to God." Therefore it is possible to hate certain people without committing a sin.

❌ Objection 3 : Further, nothing that is natural is a sin, for sin is a "wandering away from what is according to nature," according to Damascene (De Fide Orth. ii, 4,30; iv, 20). Now it is natural to a thing to hate whatever is contrary to it, and to aim at its undoing. Therefore it seems that it is not a sin to hate one's I enemy.