Proverbs 4:19

The way of the wicked [is] as darkness: they know not at what they stumble.

Ver. 19. Is as darkness.] That little light they had by nature they imprison, κατεχοντωυ , Rom 1:18 and are justly deprived of. And as for those sparkles of the light of joy and comfort that hypocrites have, it is but as a flash of lightning which is followed with a thunder clap, or like the light smitten out of the flint; (1.) they cannot warm themselves by it, nor see to direct their ways; (2.) it will quickly go out; (3.) and after that they must "lie down in sorrow." Isa 50:11

They know not at what they stumble.] They stumble sometimes at Christ himself, and at his word, "being disobedient, whereunto also they were appointed." 1Pe 2:8 A shrewd sign of reprobation. The Vulgate renders it, Ne sciunt ubi corruant. They know not how soon they may drop into hell, which even gapes for them. Isa 14:9