For a Christian, it is not enough for him to know what he is obliged to do; it is, moreover, necessary for him, by hearing the divine word from time to time, to be reminded of the importance of eternal salvation, and of the means which he ought to adopt in order to secure it. Hence the following command of St. Paul to Timothy: "Preach the word, be instant in season, out of season; reprove, entreat, rebuke in all patience and doctrine." (2 Tim 4:2)
[Our Lord gave the command], "Going, therefore, teach ye all nations...to observe all things whatsoever I have commanded you." (Mt 28:19) And should a sinner be damned through the fault of him who preaches the divine word, God will demand an account of the priest who could have announced the truths of salvation to that lost soul.
But to save souls, it is not enough to preach; it is...necessary to preach in a proper manner, [and for this] and exemplary life is necessary...St. John Chrysostom writes, "How is it possible for a priest to persuade by his words, when his acts are in opposition to his doctrine?" According to St. Paul, he who reproves in others what he himself does, condemns himself. "Thou are inexcusable, O man, whosoever thou art that judgest. For wherein thou judgest another, thou condemnest thyself." (Rom 2:1) "He," says St. Gregory, "who is not on fire does not inflame." [And] St. Frances de Sales used to say that the heart speaks to the heart...[so it is that] he who feels and practices what he preaches, shall speak to the heart of others, and shall move them to the love of God.
The preacher must have an affection for mental prayer, in which he may excite the sentiments that he will afterwards communicate to others. "In my meditation," says David, "a fire shall flame out." (Ps. 38:4)
It is necessary to preach with good intention, that is, not for temporal interest, but for the glory of God; not to attract empty praises, but to procure the salvation of souls. Hence, as the Council of Trent ordains, it is the duty of preachers to preach in a manner accommodated to the capacity of their hearers.
The persons who are present at sermons are generally...incapable of understanding flowery discourses. What a pity, sometimes, to see so many of the poor going to the sermon, and afterwards leaving the church afflicted and wearied, without having understood almost any part of the discourse. Justly has Father John d'Avila said, that they who preach in a lofty style, not intelligible to the audience, are traitors to Jesus Christ; and that, though sent by him to procure his glory, they seek only their own exaltation. Justly, too, has Father Caspar Sanzio said, that such preachers are at the present day the greatest persecutors of the Church, because by their sermons they are the cause of the perdition of many souls that would be saved by exhortations composed in a simple and apostolic style.
It is always expedient to preach in a simple, popular style, not only in the missions and spiritual exercises, but also in all sermons addressed to the people. (by popular we mean that eternal truths are expounded nakedly, subjects easily understood are explained in a simple and familiar style)
Even to the learned, sermons composed in a simple and familiar style are far more profitable than discourses written in lofty and florid language. For in sublime discourses, the mind stops to admire and criticize (and this frequently happens); but the will is left without food, and derives no profit from the sermon.
He who wishes to preach, not for the purpose of acquiring praise, but of gaining souls to God, should not seek to hear others say, "oh, what beautiful thoughts! What a splendid speaker! What a great man!" But he should desire to see all going away with their heads down, weeping over their sins, resolved to change themselves and give themselves to God.
All must be done simply and without show of art, in order to reap not applause, but fruit.
The great object should be to explain nakedly and simply the eternal truths, the importance of salvation, and to lay before the people the illusions of the devil, the dangers of perdition, and the means to be adopted in some particular cases that may occur.
It is useful to bring forward examples of the saints or examples of punishments inflicted on sinners. But above all, it is useful to inculcate things which are practical, and to repeat them several times, that they may remain impressed on the weak understanding of the poor.
