From St Maximos
They say that God allows the demons to make war on us for five reasons: the first, they say, is so that we may distinguish between virtue and vice by making war and being warred against; secondly, so that we may acquire virtue by warfare and toil, and possess it sure and steadfast; thirdly, so that we may not think highly of ourselves when we make progress in virtue, but may learn to be humble; fourthly, so that we may completely hate vice, after we have experienced it; and finally, apart from all of these, the fifth reason is so that we may not forget our frailty or the power of God which helped us to attain to passionlessness.
The First Book, p. 250
From the Gerontikon
St Synkletike said: "The better athletes become, the stronger are the adversaries against whom they contend."