Pondering on this...

No man knows how bad he is until he has tried very hard to be good. A silly idea is current that good people do not know what temptation means. This is an obvious lie. Only those who try and resist temptation know how strong it is, after all, you find out the strength of the German army after fighting against it, not by giving in. You find out the strength of a wind by walking against it, not by lying down. A man who gives into temptation after five minutes simply does not know what it would have been like an hour later. That is why bad people, in one sense, know very little about badness. They've always lived a sheltered life by always giving in. We never find the strength of evil impulse inside us until we try to fight it. And Christ, because he was the only man who knows to the full what temptation really means.

C.S Lewis. Mere Christianity