The Dhammapada
Chapter 1: “The Pairs”
8
Just as a storm cannot prevail against a rocky mountain, so Mara can never overpower the man who lives meditating on the impurities, who is controlled in his senses, moderate in eating, and filled with faith and earnest effort.
The impurities (asubha): subjects of meditation which focus on the inherent repulsiveness of the body, recommended especially as powerful antidotes to lust.