5 Let us then give heed unto Him exactly, that though late we may at length recover our sight. And how may one recover sight? If you learn how you were blinded. How then were you blinded? By your wicked desire. For the love of money, like an evil humor which has collected upon a clear eyeball, has caused the cloud to become thick.
But even this cloud may be easily scattered and broken, if we will receive the beam of the doctrine of Christ; if we will hear Him admonishing us, and saying, “Lay not up for yourselves treasures upon earth.”
“But,” says one, “what avails the hearing to me, as long as I am possessed by the desire?” Now in the first place, there will be power in the continual hearing to destroy even the desire. Next, if it continue to possess you, consider that this thing is not really so much as a desire. For what sort of desire is this, to be in grievous bondage, and to be subject to a tyranny, and to be bound on all sides, and to dwell in darkness, and to be full of turmoil, and to endure toils without profit, and to keep your wealth for others, and often for your very enemies? With what sort of desire do these things agree? Or rather of what flight and aversion are they not worthy? What sort of desire, to lay up treasure in the midst of thieves? Nay, if you dost at all desire wealth, remove it where it may remain safe and unmolested. Since what you are now doing is the part of one desiring, not riches, surely, but bondage, and affront, and loss, and continual vexation. Yet thou, were any one among men on earth to show you a place beyond molestation, though he lead you out into the very desert, promising security in the keeping of your wealth—you are not slow nor backward; you have confidence in him, and puttest out your goods there; but when it is God instead of men who makes you this promise, and when He sets before you not the desert, but Heaven, you accept the contrary. Yet surely, how manifold soever be their security below, you can never become free from the care of them. I mean, though thou lose them not, you will never be delivered from anxiety lest you lose. But there you will undergo none of these things: and mark, what is yet more, thou dost not only bury your gold, but plantest it. For the same is both treasure and seed; or rather it is more than either of these. For the seed remains not for ever, but this abides perpetually. Again, the treasure germinates not, but this bears you fruits which never die.
Source: Homilies on the Gospel of St. Matthew (New Advent)