St. John Baptist, my brethren, as you know, retired to the desert at an early age, and led there an austere and solitary life, eating coarse and unpalatable food, abstaining from wine and strong drink, cutting off all unnecessary enjoyments of the senses, and giving himself up to prayer and meditation. What was his special motive in this extraordinary course of penance? It was that he might worthily prepare himself for the office which had been as signed to him—that of disposing men's hearts to recognize and receive our Lord when he should come as their Redeemer. It was by penance alone that those hearts could be so disposed, and he was to be specially the apostle of penance; hence he had to give a signal example of it in his own person; for preaching, however eloquent, is of comparatively little effect unless the preacher practises the virtues to which he exhorts others; and the power of his preaching will be in proportion to the illustration which it finds in his own life.
Therefore, though it was not necessary for St. John, sanctified as he was even before his birth, to cut off all other sources of pleasure in order to fill his soul with the joy that comes from the love of God, and though he had no sins to atone for, for his life had been free from blame, still he took up this course of penance in order to show forth even more plainly than by his words the need that his hearers would have, in their measure, to do likewise, if they were to share in the redemption to come.
For now, as he told them, the axe was to be laid to the root of the tree. God's chosen people, the Jews, whom he had specially watched over for so many years, whom he had often chastised and corrected, and had brought back to his favor when they profited by his visitations, they were no more to be thus dealt with. The tree which had sprung from the seed of Abraham was not to be allowed any longer to stand with merely some lopping and pruning; no, now, if it still would not bring forth the good fruit of a thorough and genuine penance, it was to be cut down and cast into the fire. It was the supreme test which was approaching; if the people whom he had chosen would stand it, they should still retain their place; otherwise they should be rejected as a nation, and only those among them who would truly turn to their God should be saved.
My brethren, St. John is still preaching this doctrine of penance to us. The Church of the New Law is not on her trial, as was that of the Old; no, her Divine Founder has promised that she shall endure to the end of the world. But we, each one of us, have to take the words of his precursor to ourselves. We are called by the name of Christ; yes, but that will not save us. St. John said to the Jews: "Think not to say within yourselves, we have Abraham for our father." So we are not to think ourselves as belonging to Christ, unless we have cast out from our hearts and souls what puts a fatal obstacle to his entrance into them. His axe will be laid to our root also, unless we on our part lay the axe to the root of our sins.
What is this root of sin in us? It is just this desire of sensual indulgence against which St. John in his life as well as in his doctrine came to make the strongest of protests. If we wish not to bring forth the fruits of sin, we must lay the axe to its root. We must practise penance and mortification, not indeed always to the degree in which he practised it, but at least so far as it is necessary that we may keep the law of God. We must not dally with those things which are dangerous to us, innocent though they may be to others. Our Lord has told us that if even our eyes and hands themselves are an occasion of sin we must pluck them out or cut them off; if, then, there be anything we enjoy, but can really do with out, we must not make a pretext of the good use which we might make of it if it really is plain that we will abuse it, but must resolutely cast it away. If we would avoid the bitter fruit which will naturally grow we must lay the axe to the root of the tree.