Charles Ellicott Commentary Psalms 104:20

"Thou makest darkness, and it is night, Wherein all the beasts of the forest creep forth." — Psalms 104:20 (ASV)

Creep forth. —The word “forth” is better omitted. The Hebrew verb is that especially used of crawling animals and reptiles, and here, no doubt, is chosen to express the stealthy motion of the beasts when on the track of their prey. (compare to Job 37:8 and Job 38:40.)