When the Scripture enjoins us to conduct ourselves in such a manner toward men, as in honour to prefer one another, and faithfully to devote our whole attention to the promotion of their advantage, it gives such commands as our heart can by no means receive, without having been previously divested of its natural bias. For we are all so blinded and fascinated with self-love, that every one imagines he has a just right to exalt himself, and to undervalue all others who stand in competition with him.…The poor yield to the rich, plebeians to nobles, servants to masters, the illiterate to the learned; but there is no man who does not cherish within him some idea of his own excellence. Thus all men, in flattering themselves, carry, as it were, a kingdom in their own breast: for arrogating to themselves the height of self-gratulation, they pass censure on the understandings and conduct of others.
~ John Calvin (Romans 12)