The Catholic saint's guide to winning this spiritual battle is a prayer, the "Prayer of St. Thomas Aquinas for Purity."
St. Thomas Aquinas on fighting against lust
The prayer goes:
"Dear Jesus,
I know that every perfect gift,
and especially that of chastity,
depends on the power of Your providence.
Without You, a mere creature can do nothing.
Therefore, I beg You to defend by Your grace
the chastity and purity of my body and soul.
And if I have ever sensed or imagined anything
that could stain my chastity and purity,
blot it out, Supreme Lord of my powers,
that I may advance with a pure heart in Your love and service,
offering myself on the most pure altar of Your divinity
all the days of my life. Amen."
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