Pope St. Gregory I: “For a man is made similar to the apostate angel when he disdains to be similar to men.  Thus after possessing the merit of humility, Saul at the summit of power was inflated with the swelling of pride.  He was indeed preferred through humility, but was indeed made reprobate through pride, as the Lord bears witness when he says: ‘Was it not when you were little in your own eyes that I set you as head of the tribes of Israel?’  And a little further below: ‘Now in a marvelous manner when he seemed little before himself he was great before the Lord, but indeed when he seemed great before himself he was little before the Lord.’” (quoted by Pope St. Gregory VII, March 15, 1081)