The perfection of a Christian consists in mortifying his will for the love of Christ. Where there is no great mortification, there is no great sanctity.
-- St. Philip Neri

And of what should we be afraid? Our captain on this battlefield is Christ Jesus. We have discovered what we have to do. Christ has bound our enemies for us and weakened them that they cannot overcome us unless we so choose to let them. So we must fight courageously and mark ourselves with the sign of the most Holy Cross.
-- St. Catherine of Sienna

After you have made a decision that is pleasing to God, the Devil may try to make you have second thoughts. Intensify your prayer time, meditation, and good deeds. For if Satan's temptations merely cause you to increase your efforts to grow in holiness, he'll have an incentive to leave you alone.
-- St. Ignatius of Loyola

There is more value in a little study of humility and in a single act of it than in all the knowledge in the world.
-- St. Theresa of Avila

The devil doesn't fear austerity but holy obedience.
-- St. Francis de Sales