Again I see others stand talking while Prayer is going on; while the more consistent of them (do this) not only during the Prayer, but even when the Priest is giving the Benediction. O, horror! When shall there be salvation? When shall it be possible for us to propitiate God?— Soldiers go to their diversion, and you shall see them, all keeping time in the dance, and nothing done negligently, but, just as in embroidery and painting, from the well-ordered arrangement in each individual part of the composition, there results at once an exceeding harmony and good keeping, so it is here: we have one shield, one head, all of us (in common): and if but some casual point be deranged by negligence, the whole is deranged and is spoilt, and the good order of the many is defeated by the disorder of the one part.
And, fearful indeed to think of, here you come, not to a diversion, not to act in a dance, and yet you stand disorderly. Know you not that you are standing in company with angels? With them you chant, with them sing hymns, and do you stand laughing? Is it not wonderful that a thunderbolt is not launched not only at those (who behave thus), but at us? For such behavior might well be visited with the thunderbolt. The Emperor is present, is reviewing the army: and do you, even with His eyes upon you, stand laughing, and endure to see another laughing?
How long are we to go on chiding, how long complaining? Ought not such to be treated as very pests and nuisances; as abandoned, worthless reprobates, fraught with innumerable mischiefs, to be driven away from the Church? When will these forebear laughing, who laugh in the hour of the dread Mystery (ἑ ν ὣρᾳ φρίκης)? When refrain from their trifling, who talk at the instant of the Benediction? Have they no sense of shame before those who are present? Have they no fear of God?
Are our own idle thoughts not enough for us, is it not enough that in our prayers we rove hither and there, but laughter also must needs intrude, and bursts of merriment? Is it a theatrical amusement, what is done here? Aye, but, methinks, it is the theatres that do this: to the theatres we owe it that the most of you so refuse to be curbed by us, and to be reformed. What we build up here, is thrown down there: and not only so, but the hearers themselves cannot help being filled with other filthinesses besides: so that the case is just the same as if one should want to clean out a place with a fountain above it discharging mire; for however much you may clean out, more runs in.
So it is here. For when we clean people out, as they come here from the theatres with their filthiness, there they go again, and take in a larger stock of filthiness, as if they lived for the purpose of only giving us trouble, and then come back to us, laden with ordure, in their manners, in their movements, in their words, in their laughter, in their idleness. Then once more we begin shovelling it out afresh, as if we had to do this only on purpose that, having sent them away clean, we may again see them clogging themselves with filth.
Therefore I solemnly protest to you, the sound members, that this will be to you judgment and condemnation, and I give you over to God from this time forth, if any having seen a person behaving disorderly, if any having seen any person talking, especially in that part (of the Service), shall not inform against him, not bring him round (to a better behavior). To do this is better than prayer. Leave your prayer and rebuke him, that you may both do him good, and yourself get profit, and so we may be enabled all to be saved and to attain unto the Kingdom of Heaven, through the grace and loving-kindness of our Lord Jesus Christ, with Whom to the Father and the Holy Ghost together be glory, dominion, honor, now and ever, and world without end. Amen.
Source: Homilies on Acts (New Advent)