Charles Spurgeon Commentary Isaiah 44:16-18

"He burneth part thereof in the fire; with part thereof he eateth flesh; he roasteth roast, and is satisfied; yea, he warmeth himself, and saith, Aha, I am warm, I have seen the fire. And the residue thereof he maketh a god, even his graven image; he falleth down unto it and worshippeth, and prayeth unto it, and saith, Deliver me; for thou art my god. They know not, neither do they consider: for he hath shut their eyes, that they cannot see; and their hearts, that they cannot understand." — Isaiah 44:16-18 (ASV)

He burneth part thereof in the fire; with part thereof he eateth flesh; he roasteth roast, and is satisfied: yea, he warmeth himself, and saith, Aha, I am warm, I have seen the fire: And the residue thereof he maketh a god, even his graven image: he falleth down unto it, and worshippeth it, and prayeth unto it, and saith, Deliver me; for thou art my god. They have not known nor understood:

There must be a failure of knowledge or understanding where such folly as this is possible.