Isaiah 44 - The only reason someone does not understand the folly of their idolatry is because…

Isa 44:18 They do not know, nor do they understand, for He has smeared over their eyes so that they cannot see and their hearts so that they cannot comprehend.

The only reason someone does not understand the folly of their idolatry is because they are blinded and cannot see. Elohim has shut their eyes from seeing and their hearts from understanding (Isa 6:10, 29:10, Psalm 81:11-12).