3 Therefore, as the Apostle James says, “Let every man be swift to hear, slow to speak.” As it is also said by another man of God, “You will make me to hear joy and gladness; and the bones You have humbled will rejoice.” This is what I said: When the truth is heard, humility is preserved. And another says: “But the friend of the bridegroom stands and hears him, and rejoices greatly because of the bridegroom's voice.” Let us rejoice in the hearing that comes from the noiseless speaking of the truth within us.
For although, when the sound is outwardly uttered, as by one that reads; or proclaims, or preaches, or disputes, or commands, or comforts, or exhorts, or even by one that sings or accompanies his voice on an instrument, those who do so may fear to defile their feet, when they aim at pleasing men with the secretly active desire of human applause. Yet the one who hears such with a willing and pious mind, has no room for self-gratulation in the labors of others; and with no self-inflation, but with the joy of humility, rejoices because of the Master's words of truth.
Accordingly, in those who hear with willingness and humility, and spend a tranquil life in sweet and wholesome studies, the holy Church will take delight, and may say, “I sleep, and my heart wakes.” And what is this, “I sleep, and my heart wakes,” but just I sit down quietly to listen? My leisure is not laid out in nourishing slothfulness, but in acquiring wisdom. “I sleep, and my heart wakes.” I am still, and see that You are the Lord: for “the wisdom of the scribe comes by opportunity of leisure; and he that has little business shall become wise.” “I sleep, and my heart wakes:” I rest from troublesome business, and my mind turns its attention to divine concerns (or communications).
Source: Tractates on the Gospel of John (New Advent)