The Imitation of Christ, by Thomas a Kempis, tr. by William Benham [1886], at sacred-texts.com
It behoveth thee to learn to mortify thyself in many things, if thou wilt live in amity and concord with other men. It is no small thing to dwell in a religious community or congregation, and to live there without complaint, and therein to remain faithful even unto death. Blessed is he who hath lived a good life in such a body, and brought it to a happy end. If thou wilt stand fast and wilt profit as thou oughtest, hold thyself as an exile and a pilgrim upon the earth. Thou wilt have to be counted as a fool for Christ, if thou wilt lead a religious life.
2. The clothing and outward appearance are of small account; it is change of character and entire mortification of the affections which make a truly religious man. He who seeketh aught save God and the health of his soul, shall find only tribulation and sorrow. Nor can he stand long in peace, who striveth not to be least of all and servant of all.
3. Thou art called to endure and to labour, not to a life of ease and trifling talk. Here therefore are men tried as gold in the furnace. No man can stand, unless with all his heart he will humble himself for God's sake.