No one should flatter himself for doing anything a sinner can also do. A sinner can fast, pray, weep and mortify his flesh. This one thing he cannot do: be faithful to his Lord. Therefore we should glory in this: if we give back to the Lord the glory that is his, if we serve him faithfully and ascribe to him whatever he gives to us.
– St. Francis of Assisi in Bonaventure, The Life of St. Francis 6.3