At the beginning of the Bet Halevi’s essay on Ahavat Yisrael, Loving your fellow man, he says, “Love to everyone is a positive commandment, as it says, VeAhavta LeRe’echa Kamocha Love your friend like you love yourself.
But there are some smart people who know some pesukim. They know that in Tehilim perek 139, pasuk 21, it says
הֲלוֹא־מְשַׂנְאֶיךָ ה׳ אֶשְׂנָא
Those that hate You, God, I hate.
They even know Sefer Hinuch, Mitzvat 238, which says, when it comes to hating the wicked, there is no prohibition; what’s more, it’s actually a Mitzvah to hate them.
So now the smart people among us have their excuse. They label people as wicked, and therefore they can exercise their trait of hatred. (But, not so fast- there’s a happy ending).
The Sefer Hinuch continues with a little caveat: It’s a mitzvah to hate the wicked only after we have rebuked them on their sin many times and they didn’t do Teshuva/return.
So there is a condition. You can’t just hate any wicked person. It’s only after he doesn’t accept rebuke. The HaGaot Mamoniot, a Rishon, says the same thing.
And the Chazon Ish, one of the great poskim of yesteryear, (and a very strict rabbi), says very clearly, in perek ו, halacha ג of Hilchot Deot, that you can only hate the person after you have rebuked him, but adds
(quoting from a earlier source)-
By us, we are always considered before rebuke, because we don’t know how to rebuke.
Therefore, the wicked fellow is always considered before rebuke.
So that excuse, that it’s a Mitzvah to hate some people, because they are wicked, is gone. Rebuke is not that simple.
Even if you told him many times not to do a certain sin, you don’t really know how to rebuke. Two thousand years ago, the Gemarah said that very few people knew how to rebuke properly. It’s a talent and an art, with a science behind it, that we will discuss at a later date.
For today, the lesson is that it’s not so simple to title someone as a wicked person and be allowed to hate them.