Albert Barnes Commentary Psalms 92:7

"When the wicked spring as the grass, And when all the workers of iniquity do flourish; It is that they shall be destroyed for ever." — Psalms 92:7 (ASV)

When the wicked spring as the grass - When they grow up as plants do; when they seem to flourish and prosper. (Psalms 37:2; Psalms 37:35; Psalms 37:38). The word grass here refers to the vegetable creation generally, embracing plants and flowers of all kinds.

And when all the workers of iniquity do flourish - As plants and flowers do. They are like vigorous plants, not like the stunted and dry shrubs of the desert.

It is that they shall be destroyed for ever - The meaning here is not that the design of their being allowed to flourish in this way is that they should be destroyed, or that they are made to flourish for that purpose, but that such will be the result. They will not be made happy in another world by their wickedness, which was prosperous and achieved success here, as if God approved of their course; but the end will be that they will be destroyed forever.

The psalmist's design seems to be to turn the mind from the idea that mere external prosperity is necessarily connected with happiness, or that one who prospers in this life is safe on that account. There is another world, and there ample justice will be done to all. .