40:18-26 Whatever we esteem or love, fear or hope in, more than God, that creature we make equal with God, though we do not make images or worship them. He that is so poor, that he has scarcely a sacrifice to offer, yet will not be without a god of his own. They spared no cost upon their idols; we grudge what is spent in the service of our God. To prove the greatness of God, the prophet appeals to all ages and nations. Those who are ignorant of this, are willingly ignorant. God has the command of all creatures, and of all created things. The prophet directs us to use our reason as well as our senses; to consider who created the hosts of heaven, and to pay our homage to Him. Not one fails to fulfil his will. And let us not forget, that He spake all the promises, and engaged to perform them.
24. they—the "princes and judges" (Isa 40:23) who oppose God's purposes and God's people. Often compared to tall trees (Ps 37:35; Da 4:10).
not … sown—the seed, that is, race shall become extinct (Na 1:14).
stock—not even shall any shoots spring up from the stump when the tree has been cut down: no descendants whatever (Job 14:7; see on Isa 11:1).
and … also—so the Septuagint. But Maurer translates, "They are hardly (literally, 'not yet', as in 2Ki 20:4) planted (&c.) when He (God) blows upon them."
blow—The image is from the hot east wind (simoon) that "withers" vegetation.
whirlwind … stubble—(Ps 83:13), where, "like a wheel," refers to the rotatory action of the whirlwind on the stubble.