For who knows what is good for man while he lives the few days of his vain life, which he passes like a shadow? For who can tell man what will be after him under the sun?
Here, 1. Solomon lays down his conclusion which he had undertaken to prove, as that which was fully confirmed by the foregoing discourse: There be many things that increase vanity; the life of man is vain, at the best, and there are abundance of accidents that concur to make it more so; even that which pretends to increase the vanity and make it more vexatious. 2.
Commenting on Ecclesiastes 6:11-12
For who knoweth what is good for man in this life?.... To be in a higher or lower station of life, to live in grandeur or meanness, to be rich or poor, learned or unlearned; since that which seems most agreeable to human nature is at, ended with so much vanity, the occasion of so much sin, and often issues in ruin and misery, that...
For who knoweth, &c.--The ungodly know not what is really "good" during life, nor "what shall be after them," that is, what will be the event of their undertakings (Ecc 3:22; Ecc 8:7). The godly might be tempted to "contend with God" (Ecc 6:10) as to His dispensations; but they cannot fully know the wise purposes served by them now and hereafter.