Man and his deed are two distinct things. Whereas a good deed should call forth approbation and a wicked deed dis-approbation, the doer of the deed, whether good or wicked always deserves respect or pity as the case may be. Hate the sin and not the sinner is a precept which though easy enough to understand is rarely practised, and that is why the poison of hatred spreads in the world.
A teacher who establishes rapport with the taught, becomes one with them, learns more from them than he teaches them. He who learns nothing from his disciples is, in my opinion, worthless. Whenever I talk with someone I learn from him. I take from him more than I give him.
Whether humanity will consciously follow the law of love, I do not know. But that need not disturb me. The law will work just as the law of gravitation works whether we accept it or not.