Satan's fall was due to his pride. He hadn't killed anyone. He hadn't tempted anyone. He hadn't lied to anyone (except perhaps to himself). He simply rebelled when he recognize that he was a creation and not the Creator! He could not stand the fact that there was anyone greater than he.
Pastor George F. Parsons created this helpful diagram to show Lucifer’s five haughty "I WILLS":
As believers, we tend to think more highly of ourselves than we ought (Rom. 12:3). As James put it, we are "...like unto a man beholding his natural face in a glass: for he beholdeth himself, and goeth his way, and straightway forgetteth what manner of man he was" (Jam. 1:23-24).
So the next time you are "fessed up" (have your sins confessed - 1 Jn. 1:9), and you are walking in the Spirit and not in the flesh (Rom. 8:1-4), remember, the "mountain" you are on has steep cliffs.
The cure for pride is to compare yourself to Jesus!