John Calvin Commentary Isaiah 17:8

"And they shall not look to the altars, the work of their hands; neither shall they have respect to that which their fingers have made, either the Asherim, or the sun-images." — Isaiah 17:8 (ASV)

And he shall not look to the altars. This contrast shows more clearly that the looking he spoke of in the former verse relates strictly to hope and confidence. For he says that every kind of sinful confidence will vanish when people have learned to hope in God. Indeed, in no other way can anyone obtain clear views of God than by driving all superstitions far from themselves. We are thus taught that obstacles of this kind ought to be removed if we wish to approach God. It is vain to think of making a union between God and idols, as the Papists do, and as the Jews formerly did; for that vice is not peculiar to our age, but has prevailed in all ages. Every obstruction ought therefore to be removed, so that we may look to God with such earnestness as to have just and clear views of him, and to put our trust in him.

The work of his hands. It is for the purpose of exciting abhorrence that he calls the false gods the work of their hands, so that the Israelites, being ashamed of their folly, may shake off and drive away such a disgraceful reproach. On this vice, however, he dwells more extensively, because they were more guilty of it than of any other, and because none can be more abominable in the sight of God. There were innumerable superstitions among them, and in countless places they had set up both idols and altars, so that Isaiah had good reason for reproving and expostulating with them at great length on account of these crimes.

It might be objected that the altar at Jerusalem was also built by men, and therefore they ought to forsake it in order to approach God (Exodus 27:1). I reply, that altar was widely different from others. For although it consisted of stone and mortar, silver and gold, and was made like others by human hands, we ought not to look at the materials or the workmanship, but at God himself who was the maker, because it was built by his command.

We ought therefore to consider the essential form, so to speak, which it received from the word of God; other matters should not be considered, since God alone is the architect (Exodus 20:24, 25; Deuteronomy 27:5, 6). Other altars, though they bore some resemblance to it, should be abhorred, because they did not have the authority of the word.

This is the assessment we should make of every kind of false worship, whatever appearance of sanctity it may assume; for God cannot approve of anything that is not supported by his word.