The saints tell us that the last enemy to be defeated is wicked pride:

Our eighth and last combat is against the spirit of pride, which evil, although it is the latest in our conflict with our faults and stands last on the list, yet in beginning and in the order of time is the first: an evil beast that is most savage and more dreadful than all the former ones, chiefly trying those who are perfect, and devouring with its dreadful bite those who have almost attained the consummation of virtue (St. John Cassian, Institutes, Book XII).

Pride tries the perfect man by tempting him to take credit for his great virtue, and thus causing him to fall from the height of sanctity to the depth of perdition.

The saints who have conquered this enemy have attained holy humility, and we celebrate the nativity of such a saint today. At Matins the Church sings:

Far as the wide world reacheth, born of woman,
Holier was there none than John the Baptist;
Meetly in water laving him who cleanseth
Man from pollution.

Consider the sanctity of this man whom our Lord confessed to be the greatest among those born of a woman! Yet we see his greatness in his humility. He rejoiced when his own followers left him to follow our Lord. He said: “He must increase: but I must decrease” (Jn. iii. 30). We too should rejoice when others give glory to God instead of ourselves. Not only that, we should pray for the grace to prefer that others receive praise according to the Litany of Humility:

That others may be loved more than I, Jesus, grant me the grace to desire it.
That others may be esteemed more than I, Jesus, grant me the grace to desire it.
That in the opinion of the world, others may increase and I may decrease, Jesus, grant me the grace to desire it.
That others may be chosen and I set aside, Jesus, grant me the grace to desire it.
That others may be praised and I unnoticed, Jesus, grant me the grace to desire it.
That others may be preferred to me in everything, Jesus, grant me the grace to desire it.

Humility is in confessing that God is all and we are nothing. When we know the greatness of God, we know the nothingness of fallen human nature.

St. Thomas says that humility means conformity with the truth (II-II q161). St. John confessed the truth, and died for it. He reached the heights of humility when he knew that every good within him is from God, and every evil is his own creation. This is why all the saints confessed that they were great sinners, despite their holiness.

On this great feast let every soul beseech the Holy Forerunner that he obtain for us from God the gift of holy humility. Holy John the Baptist, pray for us.