8 Therefore that this may not be so, let us lay aside our filthy garments, let us put on the armor of light, and the glory of God will wrap us around. For what is even grievous in the injunctions? Or what is there not easy? Hear, for instance, the prophet speaking, and then you shall know the easiness thereof. “Neither though thou bow as a collar your neck, and strew beneath you sackcloth and ashes, not even so shall you call a fast acceptable; but loose every bond of iniquity, unloose the twisted knots of oppressive bargains.”
See a prophet's wisdom, how stating first whatever was irksome, and removing it, he exhorts them to obtain salvation by the duties that are easy; signifying, that God needs not toils, but obedience.
Then implying that virtue is easy, but vice grievous and galling, he makes it out by the bare names; “For,” says he, “vice is a bond,” and “a twisted knot,” but virtue is a disengagement and release from all these.
“Tear in sunder every unjust compact;” thus calling men's bills about the interest due to them, and the sums they have lent.
“Set at liberty them that are bruised;” them that are afflicted. For such a being is the debtor; when he sees his creditor, his mind is broken, and he fears him more than a wild beast.
“Bring in the poor that are cast out to your house; if you see one naked, clothe him, and them that belong to your seed you shall not overlook.”
Now in our late discourse which we made unto you when declaring the rewards, we showed the wealth arising from these acts; but now let us see if any of the injunctions be grievous, and transcending our nature. Nay, nothing of the kind shall we discover, but quite the contrary; that while these courses are very easy, those of vice are full of labor. For what is more vexatious than to be lending, and taking thought about usuries and bargains, and demanding sureties, and fearing and trembling about securities, about the principal, about the writings, about the interest, about the bondsmen?
For such is the nature of worldly things; yea, nothing is so unsound and suspicious as that which is accounted security, and contrived for that purpose; but to show mercy is easy, and delivers from all anxiety.
Let us not then traffic in other men's calamities, nor make a trade of our benevolence. And I know indeed that many hear these words with displeasure; but what is the profit of silence? For though I should hold my peace, and give no trouble by my words, I could not by this silence deliver you from your punishment; rather it has altogether the opposite result; the penalty is enhanced, and not to you only, but to me also, does such a silence procure punishment. What then signify our gracious words, when in our works they help us not, but rather do harm? What is the good of delighting men in word, while we vex them in deed, bringing pleasure to the ears, and punishment to the soul? Wherefore I must needs make you sorry here, that we may not suffer punishment there.
Source: Homilies on the Gospel of St. Matthew (New Advent)