Albert Barnes Commentary Psalms 104:23

"Man goeth forth unto his work And to his labor until the evening." — Psalms 104:23 (ASV)

Man goeth forth ... - Man is now seen to go forth from his dwelling, and he appears on the stage to perform his daily toil, until evening comes, and then again he gives way to the beasts of night. Thus the scene is ever varying – showing how full of animated existence the earth is; how varied are the occupations of its different inhabitants; and how the varieties of being are adapted to its own varied condition in the alternations of day and night.