The conclusion of this cynical line of argument is peace and joy. In verses 18–20, the crucial phrases are these: and given him power to eat of it and this is the gift of God. God, as part of the goodness of His grace, keeps a man occupied with his stuff, giving him joy. The fact that some men can just take it as it comes, without agonizing all the time over the ultimate meaning of things, is the gift of God (v. 20).
