Albert Barnes Commentary Proverbs 5:21

"For the ways of man are before the eyes of Jehovah; And he maketh level all his paths." — Proverbs 5:21 (ASV)

One more warning. The sin is not against man, nor dependent on man’s detection only. The secret sin is open before the eyes of Yahweh. In the balance of His righteous judgment are weighed all human acts.

Pondereth - Note the recurrence of the word used of the harlot herself (see Proverbs 1:6 note): she ponders not, God does.