Ecclesiastes 3:9 - Matthew Poole's English Annotations on the Holy Bible

Seeing then all actions and events in the world are out of man's power, and no man can at any time do or enjoy any thing at his pleasure, but only what and when God pleaseth, as hath been now shown in many particulars, and it is as true and certain in all others, hence it follows that all men's labours, of themselves, and without God's help and blessing, are unprofitable, and utterly insufficient to make them happy.