“If good deeds done according to feelings of the heart brought salvation, then Christ’s coming would have been superfluous…  …Such is the natural quality of all bodily podvigs/struggles and visible good deeds. If we think that doing them is our sacrifice to God, and not just reparation for our immeasurable debt, then our good deeds and podvigs become the parents in us of soul-destroying pride.”
(St. Ignatius Brianchaninov)