Purity of intention consists undoing everything from a simple desire to please God…
The prophet Aggaeus says that works, however holy in themselves, if not done for God, are nothing better than a bag full of holes; which means, that they are all lost directly, and that no good comes of them. On the contrary, every action done with an intention of pleasing God, of however little value in itself, is worth many works done without such pure intention.
St. Alphonsus Ligouri