Silence is a virtue that leads the teacher to avoid speaking when he should not speak and to speak when he should not be silent.
This virtue, therefore, includes two functions. It teaches the art of being silent and that of speaking opportunely. Thus it causes the teacher to avoid two opposite defects that it condemns: taciturnity and loquacity.
The first effect of Silence produces order and calm in the classroom, insures the progress and advancement of the students, gives the teacher some rest, and preserves his health; three things that a teacher cannot afford to neglect without exposing himself to serious consequences.
Indeed, if he speaks too much, the students will do the same. They will ask and answer questions out of turn; they will meddle in what is none of their business; they will excuse themselves and try to excuse others; the class will resound with a steady hum.
Moreover, experience shows that the teachers who talk a lot are hardly listened to and that little account is taken of what they say. But if they speak rarely and to the point, their students pay attention to what they are told, like it, remember it, and profit by it.
Experience also shows that teachers who like to talk too much live in perpetual agitation and weaken their lungs severely. Teaching, in itself, is very taxing; to devote himself to it properly, no doubt a good teacher will willingly sacrifice himself; but he must do so prudently. Hence he avoids all imprudence and in particular eschews any manner of teaching that proves injurious to his health without being truly useful.
The class signals that we use afford us the great advantage of keeping Silence while teaching. These signals have been established so as to warn and correct the students and to indicate to them what they have to do; thus the teacher needs to speak only when he cannot make the children understand by signs what he wants of them. These signals, while reminding the teacher to refrain from speaking, at the same time indicate to him to speak when the signals do not suffice. This is where the teacher begins to apply the second function of Silence.
But this he should do only on three occasions: in reading, to call attention to mistakes that no student can correct and to give needed explanations, warnings, orders, and prohibitions; then during catechism, to explain the text and to help the students answer properly; and finally, during the morning and evening prayers, to exhort the students and to offer some reflections for them. On these occasions he should say only what is strictly necessary. If he spoke more than this, he would offend against the first aspect of the virtue of Silence.
Furthermore, the main goal of the teacher is to bring up the student in the Christian virtues. In general, he should enlighten their minds and move their hearts by means of these truths that he must teach them. In instructing them, he should prepare himself, as we have already mentioned in our first letter and as we will explain more fully when treating of the virtue of Prudence. To make his language more appealing, he should seek to convince himself of that with which he wishes to inspire his disciples. "If you wish to persuade," says Saint Bernard (On the Song of Songs, sermon 59, number 3), "it is rather by affectionate sentiments than by studied declamations that you will succeed in this." Indeed, many examples prove that while a skillful and eloquent teacher exhausts himself in vain by efforts that are all the more wearing as true zeal enters less into them, another teacher, perhaps much inferior in talent but fully convinced of what he teaches, will bring about the most salutary results.
A good teacher will, in general, consider as faults against Silence that should be avoided:
I tell you, on the day of judgment,
you will have to give an account for every careless word you utter (Matthew 12:36).
But as for you, teach what is consistent with sound doctrine (Titus 2:1).
When you speak, says Saint Bernard, do not let your words come rushing out; utter only true and weighty words; speak only of God or for God.
[Cum loqueris, sint verba dura, rara, vera, ponderosa et de Deo.]