Joseph Benson's Commentary of the Old and New Testaments - Isaiah 40:18
Isaiah 40:18. To whom then will ye liken God? This is a proper inference from the foregoing discourse of God’s infinite greatness; from whence he takes occasion to show both the folly of those that make mean and visible representations of God, and the utter inability of men or idols to give any opposition to God. And this discourse, concerning the madness of idolaters, prosecuted both here and in the following chapter, was designed by God as a necessary antidote, whereby the Jews might be... read more
Albert Barnes' Notes on the Whole Bible - Isaiah 40:18
To whom then will ye liken God? - Since he is so great, what can resemble him? What form can be made like him? The main idea here intended to be conveyed by the prophet evidently is, that God is great and glorious, and worthy of the confidence of his people. This idea he illustrates by a reference to the attempts which had been made to make a representation of him, and by showing how vain those efforts were. He therefore states the mode in which the images of idols were usually formed, and... read more