Ye shall conceive chaff. He now addresses his discourse to the enemies of the Church, whose insolence, he says, is foolish and to no purpose; for when God shall have brilliantly displayed his power, they shall know that their efforts will be fruitless, and that they will accomplish nothing, even though they be leagued together in vast crowds. The Lord laughs at their madness, in thinking that everything is in their power, when he can instantly, by the slightest expression of his will, restrain and destroy them, though they may be defended by a very powerful army. It is customary in the Scriptures to employ the word conceptions for denoting the designs and efforts of men. (Job 15:35; Psalm 7:14; Isaiah 26:17, and 59:4.) The metaphor is taken from pregnant women. Men are said to "conceive" and to "bring forth," when they attempt anything; but he declares that their "conception" shall be fruitless, and that they shall also "bring forth" to no purpose, for whatever they undertake shall be unsuccessful. There is nothing, therefore, in the brilliant military forces of our adversaries that ought to alarm us; for, although God may permit them for a time to bustle, and toil, and rage, yet God will at length turn into "chaff" all their rash and daring attempts. Let us learn that what Isaiah foretold about Sennacherib relates to all the adversaries of believers and of the Church. The fire of your breath shall devour you. That they "shall be devoured by the fire of their breath" is usually explained to mean, "Your breath, like fire, shall devour you." But that is an unsuitable and even absurd comparison, and the true meaning readily suggests itself, "The fire kindled by your breath shall devour you." We commonly kindle a fire by blowing, and therefore he declares, that the fire which wicked men have blown by their wicked contrivances shall be destructive to them, because it shall consume them. It is the same statement which is often conveyed by a variety of metaphors in Scripture. "They shall fall into the pit which they have digged. They are entangled in a net which they had prepared for others. The sword which they had drawn hath entered into their own bowels. Their arrow hath been turned back to pierce their own hearts." (Psalm 7:15; 37:15; 57:6.) Thus the Prophet shews that the wicked tyrant who laid waste Judea and besieged Jerusalem with a numerous army, and all others who in like manner are adversaries of the Church, bring down destruction on themselves, and will at length be destroyed; and, in short, that they will be consumed by that "fire" which they have kindled.

Ye shall conceive chaff - An address of God to the Assyrians. The figure is one that denotes that their counsels would be in vain. Chaff and stubble are used in the Scriptures, in contrast with grain, to denote anything which is not solid, nutritious, or substantial; then anything which is frivolous, useless, vain. A similar image occurs in Isaiah 26:18 (see the note on that place; compare Isaiah 59:4).
Your breath as fire shall devour you - The word 'breath' here (רוח rûach, spirit) is evidently used in the sense of the Θυμός thumos, and denotes anger, as in Isaiah 30:28. It refers to the haughty and arrogant spirit of Sennacherib; the enraged and excited mind intent on victory and plunder. The sense is, that his mind, so intent on conquest - so proud, excited, and angry, would be the means of his own destruction. Lowth proposes to read 'my spirit,' but for this change there is no authority from manuscripts (see the notes at Isaiah 1:31).

Your breath "And my spirit" - "For רוחכם ruchechem, your spirit, read רוחי כמו ruchi kemo. "Secker. Which reading is confirmed by the Chaldee, where מימרי meymri, "my word, "answers to רוחי ruchi, "my spirit."

(q) Ye shall conceive chaff, ye shall bring forth stubble: your breath, [as] fire, shall devour you.
(q) This is spoken against the enemies, who thought all was their own, but he shows that their enterprise will be in vain, and that the fire which they had kindled for others would consume them.

Ye shall conceive chaff, ye shall bring forth stubble,.... Signifying that all the counsels, designs, and schemes, of the antichristian party, to continue themselves in their present state, and save themselves from ruin, as well as utterly to destroy the interest of Christ, would be weak, vain, and fruitless; their conceptions and actions, their purposes and attempts, would be alike; would be abortive, like chaff and stubble, and only serve as such for their own destruction:
your breath as fire shall devour you; or, "your spirit" (a); your pride and haughtiness, in self praises, commendations, and glorying; your rage, wrath, and fury, against the saints; your blasphemy against God and Christ shall be the reason why the fire of God's wrath shall consume you. The Targum is,
"you have thought for yourselves, O ye people, thoughts of wickedness; ye have done for yourselves evil works; because of your evil works, my Word shall destroy you, as a whirlwind the stubble;''
Christ, the essential Word of God.
(a) "spiritus vester", V. L. Pagninus, Montanus, &c.

Ye--the enemy.
conceive chaff-- (Isaiah 26:18; Isaiah 59:4).
your breath--rather, your own spirit of anger and ambition [MAURER], (Isaiah 30:28).

After the prophet has heard this from Jehovah, he knows how it will fare with them. He therefore cries out to them in triumph (Isaiah 33:11), "Ye are pregnant with hay, ye bring forth stubble! Your snorting is the fire that will devour you." Their vain purpose to destroy Jerusalem comes to nothing; their burning wrath against Jerusalem becomes the fire of wrath, which consumes them (for chashash and qash, see at Isaiah 5:24).

Stubble - Instead of solid corn. Your great hopes and designs, shall be utterly disappointed. Your breath - Your rage against my people shall bring ruin upon yourselves.