Yeah, Rollo has a very warped view of good and evil. Basically, he views that since he's a man of God, that means he can't do wrong because it's all "in service of the Lord". It's kind of a power trip. Like those rulers who think that because they're in the position they are, it means that they decide what's right and what's wrong. Essentially, he views that what's good for him is right and what's bad for him was wrong. The narrator even said he said that he saw corruption and sin everywhere but in himself.
But here's an interesting thing, he became conscious of what he considered to be his own wickedness. He viewed Esmerelda as evil by default simply because she was a gypsy, and thus he saw his lust for her as sinful (the song Hell Fire), but decided that he didn't care and was willing to do sinful things and be evil himself to get her, his excuse for his actions being "The devil is stronger than a man."