Saint Thomas Becket, martyr: "Whoever hates his brother is in darkness"

the darkness has blinded his eyes.

-- 1 Jn 2:3-11

Deliberate hatred is contrary to charity. Hatred of the neighbor is a sin when one deliberately wishes him evil. Hatred of the neighbor is a grave sin when one deliberately desires him grave harm. "But I say to you, Love your enemies and pray for those who persecute you, so that you may be sons of your Father who is in heaven."

-- CCC 2303