He opposes three chief virtues, alms, prayer, and fasting, to three evil things against which the Lord undertook the war of temptation. For He fought for us in the wilderness against gluttony; against covetousness on the mount; against false glory on the temple. It is alms that scatter abroad against covetousness which heaps up; fasting against gluttony which is its contrary; prayer against false glory, seeing that all other evil things come out of evil, this alone comes out of good; and therefore it is not overthrown but rather nourished of good, and has no remedy that may avail against it but prayer only.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).
Also cites: Hom. xv