A moderately bad man knows he is not very good: a thoroughly bad man thinks he is alright. This is common sense really. You understand sleep when you are awake, not well you are sleeping.
C. S. LewisA man who was merely a man and said the sort of things Jesus said would not be a great moral teacher. He would either be a lunatic - on a level with the man who says he is a poached egg - or else he would be the Devil of Hell. You must make your choice. Either this man was, and is, the Son of God; or else a madman or something worse. You can shut him up for a fool; you can spit at him and kill him as a demon; or you can fall at his feet and call him Lord and God. But let us not come with any patronizing nonsense about his being a great human teacher. He has not left that open to us.
C. S. Lewis