"Purity consists above all in holding back the impulses of sense-desire, which has as its object what is bodily and sexual in man. Purity is a variant of the virtue of temperance." Source: Pope St. John Paul II, Man and Woman He Created Them, Pauline Books and Media, 2006.
"Join humility to temperance, for the one is useless without the other." Source: St. John Climacus, The Ladder of Divine Ascent
"It is when I possess least that I have the fewest worries and the Lord knows that, as far as I can tell, I am more afflicted when there is excess of anything than when there is lack of it." Source: Saint Teresa of Avila, The Way of Perfection, Dover Thrift Editions, 2012. [...]
"One must avoid excess, either in the time given to them, or the amount of interest they absorb; for if too much time be given up to such things, they cease to be a recreation and become an occupation; and so far from resting and restoring mind or body, they have precisely the contrary effect." [...]
"It is by this capacity (reason and understanding) the soul drinks in wisdom, and becomes endowed with those virtues by which, in prudence, fortitude, temperance, and righteousness, it makes war upon error and the other inborn vices, and conquers them by fixing its desires upon no other object than the supreme and unchangeable Good." [...]