Prayer for Chastity by St. Thomas Aquinas

Dearest Jesus! I know well that every perfect gift, and above all others that of chastity, depends upon the most powerful assistance of Your Providence, and that without You a creature can do nothing. Therefore, I pray You to defend, with Your grace, chastity and purity in my soul as well as in my body. And if I have ever received through my senses any impression that could stain my chastity and purity, may You, Who are the Supreme Lord of all my powers, take it from me, that I may with an immaculate heart advance in Your love and service, offering myself chaste all the days of my life on the most pure altar of Your Divinity.

Amen.