Mortification

77. We may say with St. Thomas, [12, qu. iv, art. 2] that this craving of ours to be esteemed, respected and honoured is an effect of Original Sin, like concupiscence which remains to us even after our Baptism; but God has ordained that these appetites and desires should remain in us in order that we might have occasion of mortifying ourselves and that by such means we might gain the kingdom of Heaven.
We need not be astonished nor sad when we feel these instincts within us. They belong to the wickedness of our corrupt nature and are remnants of the temptation of our first parents by the serpent, when he said to them: "And you shall be as gods." [ Gen. iii, 5] Therefore I repeat that these desires which arise from the weakness and depravity of our human nature must be borne with patience. If these desires gain the mastery over us, it is because we have encouraged and given way to them; and a bad habit which we have formed ourselves can only be cured by ourselves, and therefore the mortification of the same also lies with us. This mortification of the senses, inspired by humility, is taught by Christ in the self-denial which He imposed upon us when He said: "If any man will follow Me) let him deny himself." [Matt. xvi, 24] And therefore I must draw this conclusion, that if I will not mortify myself with humility-----that is to say, crush my self-love and craving for esteem-----I shall be excluded as a follower of Jesus Christ, and by such an exclusion I shall also forfeit His grace and be eternally exiled from participating in His glory.

But in order to practice it, it is necessary for me to do violence to myself, as it is written: "The kingdom of heaven suffereth violence) and the violent bear it away." [Matt. xi, 12] Who can obtain salvation) except by doing violence to himself?