St. Vincent de Paul made himself so completely master of his tongue, that useless or superfluous words were rarely heard from his mouth, and never a single one inconsiderate, contrary to charity, or such as might savor of vanity, flattery, or ostentation. It often happened that after opening his mouth to say something unusual that came into his mind, he closed it suddenly, stifling the words, and apparently reflecting in his own heart, and considering before God whether it was expedient to say them. He then continued to speak, not according to his inclination, for he had none, but as he felt sure would be most pleasing to God.
When anything was told him which he already knew, he listened with attention, giving no sign of having heard it before. He did this to mortify self-love, which always makes us desire to prove that we know as much as others.
When he found himself overwhelmed with excessive work, he did not complain, but his ordinary words were: “Blessed be God! we must accept willingly all that He deigns to send us.”
St. Aloysius Gonzaga, when about to converse with any one, fervently repeated this prayer: Pone Domine, custodiam, ori meo, etc. — Set a watch, O Lord, before my lips, etc. (Ps 141:3)
Text from A Year With the Saints (New York: P.J. Kenedy & Sons, 1891).