9 What profit has the worker from that in which he labors?
10 I have seen the God-given task with which the sons of men are to be occupied.
11 He has made everything beautiful in its time. Also He has put eternity in their hearts, except that no one can find out the work that God does from beginning to end.
12 I know that nothing is better for them than to rejoice, and to do good in their lives,
13 and also that every man should eat and drink and enjoy the good of all his labor—it is the gift of God.
Verse 9 is asking what profit man receives for all his work.
God has given man an awareness of Himself (v.11), but it is suppressed by our sin nature (Romans 1:18-21). … Though man has an awareness of eternity, of “something more,” he cannot figure out God’s place in its entirety (thus his frustration and sense of futility). — Grace, page 1171.
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God has not created man without the ability to appreciate the importance of what he is doing. He has implanted eternity in the heart of man. To give into the heart is a Hebraism for giving or speaking in a flattering way. Man alone has within him the ability to appreciate what God is doing. It is beyond man to reason out the significance of each time event. He cannot know, even if he torments himself, the hours when events will come to pass. Indeed, to attempt the unraveling of the future is an exercise forbidden to man (Isaiah 47:12). He can, however, in the spirit of Romans 8:28 know that God is working all things together for His good and with the knowledge of that reality he can enter into the path of profit and joy. — KJV Commentary, page 740.
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The decision to break with anxiety and travail is not a decision that man is free to make. It is not in his ability to do it. He may will it, but he cannot perform it (Romans 7:18). The ability to enjoy the things that are presented and to have a joyful heart is the gift of God. — KJV Commentary, page 740.
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The eating and drinking and toiling, and the enjoyment resulting therefrom means legitimate labor as man’s daily duty; but not as the end, or purpose, of his being. — Williams, page 441.
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