To trust in works, which one ought to do in fear [of God], is equivalent to giving oneself the honor and taking it from God, to whom fear is due in connection with every good work. But this is completely wrong, namely to please oneself, to enjoy oneself in one’s own works, and to adore oneself as an idol. He who is self-confident and without fear of God, however, acts entirely in this manner. For if he had fear he would not be self-confident, and for this reason he would not be pleased with himself, but he would be pleased with God.
— Martin Luther, Luther’s Works, ed Pelikan & Lehmann (Phil: Fortress Press, 58-72), 31.46.