John Calvin Commentary Isaiah 40:25

"To whom then will ye liken me, that I should be equal [to him]? saith the Holy One." — Isaiah 40:25 (ASV)

And to whom will ye liken me? He repeats the former statement (Isaiah 40:18), in which He said that the Lord would not allow Himself to be compared to idols. This was so that the Jews might not in any way diminish His power because they had been held captive for so long by unbelievers, or think that idols are anything of significance because of the prosperity of their worshippers, whom they were forced to serve. For by reasoning this way about the power of the true God and of idols, they would have equated Him with idols.

For this reason He repeats, as if in indignation, To whom will ye liken me?—as if to say, “Will you rob Me of My majesty by your comparisons?” For although people have various thoughts about God and transform Him according to their imagination, yet He remains like Himself, for He does not change His nature because of human inventions.

Saith the Holy One. He appropriately applies to God the term Holy, by which title He indirectly blames or accuses the Jews of shameful ingratitude if, since they have been set apart by Him, they do not sanctify Him in return.

No holiness will be found in the gods of the Gentiles; they are mere human inventions. Therefore, a grievous injury is done to God, and He is shamefully degraded from His rank, when idols are set up against Him, and when it becomes a subject of debate whether they can do more than God Himself.