Imitation of Christ

Quando homo incipit tepescere, tunc parvum metuit laborem, et externam accipit consolationem. Sed quando perfecte incipit se vincere, et viriliter in via Dei ambulare, tunc minus ea reputat, quæ sibi prius gravia esse sentiebat. 

When a man begins to grow lukewarm, then he fears a little labor, and willingly accepts outward consolation; but when he begins perfectly to conquer himself and to walk manfully in the way of God, then he counts as nothing those things which before seemed to be so grievous to him.

Imitation of Christ, II, 4:3