Matthew 6:19

Thus, after He hath cast out the disease of vainglory, and not before, He seasonably introduces His discourse of voluntary poverty. For nothing so trains men to be fond of riches, as the fondness for glory. This, for instance, is why men devise those herds of slaves, and that swarm of eunuchs, and their horses with trappings of gold, and their silver tables, and all the rest of it, yet more ridiculous; not to satisfy any wants, nor to enjoy any pleasure, but that they may make a show before the multitude. Now above He had only said, that we must show mercy; but here He points out also how great mercy we must show, when He saith, "Lay not up treasure." For it not being possible at the beginning to introduce all at once His discourse on contempt of riches, by reason of the tyranny of the passion, He breaks it up into small portions, and having set free the hearer's mind, instills it therein, so as that it shall become acceptable. Wherefore, you see, He said first "Blessed are the merciful;" and after this "Agree with thine adversary;" and after that again, "If any one will sue thee at the law and take thy coat, give him thy cloak also;" but here, that which is much greater than all these. […]

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," saith 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 thee, 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 thy wealth for others, and often for thy 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 thou 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 thee a place beyond molestation, though he lead thee out into the very desert, promising security in the keeping of thy wealth,-thou art not slow nor backward; thou hast confidence in him, and puttest out thy goods there; but when it is God instead of men who makes thee this promise, and when He sets before thee not the desert, but Heaven, thou acceptest the contrary. Yet surely, how manifold soever be their security below, thou canst never become free from the care of them. I mean, though thou lose them not, thou wilt never be delivered from anxiety lest thou lose. […]

Saying, Lay not up for yourselves treasure on earth, He adds, where rust and moth destroy, in order to show the insecurity of that treasure that is here, and the advantage of that which is in Heaven, both from the place, and from those things which harm. As though He had said; Why fear you that your wealth should be consumed, if you should give alms? Yea rather give alms, and they shall receive increase, for those treasures that are in Heaven shall be added to them, which treasures perish if ye do not give alms. He said not, You leave them to others, for that is pleasant to men.

(ap. Anselm.) Here are three precepts according to the three different kinds of wealth. Metals are destroyed by rust, clothes by moth; but as there are other things which fear neither rust nor moth, as precious stones, He therefore names a common damage, that by thieves, who may rob wealth of all kinds. a Allegorically; Rust denotes pride which obscures the brightness of virtue. Moth which privily eats out garments, is jealousy which frets into good intention, and destroys the bond of unity. Thieves denote heretics and demons, who are ever on the watch to rob men of their spiritual treasure.

Lay not up to yourselves treasures. Above, the Lord determined that we should not do works for the sake of glory. Here he teaches that we should not set riches as the end of our good works. For there are two evils — covetousness and …

"Lay not up for yourselves treasures upon earth, where moth and corruption doth destroy, and where thieves break through and steal: but lay up for yourselves treasures in heaven, where neither moth nor corruption doth destroy, and where thieves do not break through nor steal. …

Lay not up for yourselves treasures upon earth,.... Meaning either treasures that are of an earthly nature and kind, the more valuable and excellent things of the earth, worldly wealth and riches; or the things and places, in which these are laid up, as bags, chests, or coffers, barns and other treasuries, private or public.

Lay not up for yourselves treasures upon earth - Treasures, or wealth, among the ancients, consisted in clothes or changes of raiment, as well as in gold, silver, gems, wine, lands, and oil. It meant an abundance of “anything” that was held to be conducive to the ornament or comfort of life. As the Orientals delighted much in display, in splendid equipage, and costly garments, their treasures, in fact, consisted much in beautiful and richly-ornamented articles of apparel.

There are three subjects brought before us in this part of our Lord’s sermon on the mount. These three are fasting, worldliness, and singleness of purpose in religion. Fasting, or occasional abstinence from food in order to bring the body into subjection to the spirit, is a practice frequently mentioned in the Bible, and generally in connection with prayer. David fasted when his child was sick; Daniel fasted when he sought special light from God; Paul and Barnabas fasted when they appointed elders; Esther fasted before going in to Ahasuerus.

In Jas 5:2 there is an evident reference to our Lord's words here. and rust--any "eating into" or "consuming"; here, probably, "wear and tear." doth corrupt--cause to disappear. By this reference to moth and rust our Lord would teach how perishable are such earthly treasures. and where thieves break through and steal--Treasures these, how precarious!

There are three subjects brought before us in this part of our Lord’s sermon on the mount. These three are fasting, worldliness, and singleness of purpose in religion. Fasting, or occasional abstinence from food in order to bring the body into subjection to the spirit, is a practice frequently mentioned in the Bible, and generally in connection with prayer. David fasted when his child was sick; Daniel fasted when he sought special light from God; Paul and Barnabas fasted when they appointed elders; Esther fasted before going in to Ahasuerus. It is a subject about which we find no direct command in the New Testament. It seems to be left to everyone’s discretion, whether he will fast or not. In this absence of direct command we may see great wisdom. Many a poor man never has enough to eat, and it would be an insult to tell him to fast: many sick people can hardly be kept well with the closest attention to diet, and could not fast without bringing on illness. It is a matter in which everyone must be persuaded in their own mind, and not rashly condemn others who do not agree with him. One thing only must never be forgotten: those who fast should do it quietly, secretly and without ostentation. Let them not “appear to men to fast.” Let them not fast to man, but to God. Worldliness is one of the greatest dangers that beset man’s soul. It is no wonder that we find our Lord speaking strongly about it: it is an insidious, specious, plausible enemy; it seems so innocent to pay close attention to our business! It seems so harmless to seek our happiness in this world, so long as we keep clear of open sins! Yet here is a rock on which many make shipwrecked to all eternity. They “lay up treasure on earth,” and forget to “lay up treasure in heaven.” May we all remember this! Where are our hearts? What do we love best?

Lay not up for yourselves treasures upon earth - What blindness is it for a man to lay up that as a treasure which must necessarily perish! A heart designed for God and eternity is terribly degraded by being fixed on those things which are subject to corruption. “But may we not lay up treasure innocently?” Yes. 1st. If you can do it without setting your heart on it, which is almost impossible: and 2dly. If there be neither widows nor orphans, destitute nor distressed persons in the place where you live. “But there is a portion which belongs to my children; shall I distribute that among the poor?” If it belongs to your children, it is not yours, and therefore you have no right to dispose of it. “But I have a certain sum in stock, etc.; shall I take that and divide it among the poor?” By no means; for, by doing so, you would put it out of your power to do good after the present division: keep your principal, and devote, if you possibly can spare it, the product to the poor; and thus you shall have the continual ability to do good. In the mean time take care not to shut up your bowels of compassion against a brother in distress; if you do, the love of God cannot dwell in you. Rust - Or canker, βρωσις, from βρωσκω, I eat, consume. This word cannot be properly applied to rust, but to any thing that consumes or cankers clothes or metals. There is a saying exactly similar to this in the Institutes of Menu: speaking of the presents made to Brahmins, he says, “It is a gem which neither thieves nor foes take away, and which never perishes.” Chapter of Government, Institute 83. Where thieves do not break through - Διορυσσουσι, literally dig through, i.e. the wall, in order to get into the house. This was not a difficult matter, as the house was generally made of mud and straw, kneaded together like the cobb houses in Cornwall, and other places. See Clarke on Mat 7:27 (note).