When tested by some trial you should try to find out not why or through whom it came, but only how to endure it gratefully, without distress or rancor.
Fasting is the champion of every virtue, the beginning of the struggle, the crown of the abstinent, the beauty of virginity and sanctity, the resplendence of chastity, the commencement of the path of Christianity, the mother of prayer, the well-spring of sobriety and prudence, the teacher of stillness, and the precursor of all good works. Just as the enjoyment of light is coupled with healthy eyes, so desire for prayer accompanies fasting that is practiced with discernment.
A great effort and much toil are needed in prayer before we can reach a state in which our mind is no longer troubled, and so attain the inward heaven of the heart where Christ dwells. As St. Paul says, 'Do you not realize that Christ dwells within you, unless you are worthless?' (cf. 2 Cor. 13:5).
'When ye suffer for righteousness’ sake, blessed are ye, seeing that ye are become partakers of the sufferings of Christ' (1 Peter 3:14; 4:13). Therefore, when you are unoppressed do not rejoice; and when tribulations come upon you, do not be sullen, accounting them as foreign to God’s way. For His path has been trodden from the ages and from all generations by the cross and by death. But how is it with you, that the afflictions on the path seem to you to be off the path? Do you not wish to follow the steps of the saints? Or have you plans for devising some way of your own, and of journeying therein without suffering?
But if you give a strong body rest and ease and idleness, all the passions dwelling in the soul are intensified. Then, even if the soul has a great desire for good, even the very thought of the good that is desired will be taken from you.
A single word made the thief pure and holy, despite all his previous crimes, and brought him into paradise (cf. Luke 23:42-43). A single ill-advised word prevented Moses from entering the promised land (cf. Num. 20:12). We should not suppose, then, that garrulity is only a minor disease. Lovers of slander and gossip shut themselves out of the kingdom of heaven.
There is a sin which is always 'unto death' [1 Jn 5:16]; the sin which we have not repented. Even a saint's prayers will not be heard for the unrepented sin. The person who repents correctly does not imagine that his sins are cancelled through his own effort; but knows that through this effort he makes peace with God.