Albert Barnes Commentary Psalms 104:14

"He causeth the grass to grow for the cattle, And herb for the service of man; That he may bring forth food out of the earth," — Psalms 104:14 (ASV)

He causes the grass to grow for the cattle—Out of the earth, every variety of food necessary for the various orders of beings that are placed upon it is caused to grow. The idea here is not merely that of “abundance;” it is also that of “variety:” the needs and tastes of all have been consulted in the productions of the earth.

The one earth—the same earth—has been made to produce the endless varieties of food required for the creatures that have been placed on it. The word “grass” here refers to all the vegetable productions needed for cattle.

And herb for the service of man—(Genesis 1:29). The word “herb” here would include every green plant or vegetable, or all that the earth produces for the food of man. This, of course, refers to the earth as it came from the hand of God and to the original arrangement, before permission was given to man to eat the flesh of animals (Genesis 9:3).

The word translated “service” might be rendered “culture,” as if man was to cultivate it for his use, not that it was to be produced spontaneously, as food for cattle is.

That he may bring forth food out of the earth—Hebrew, “bread.” That is, that by culture he may bring forth that which would make bread.