Shared ground
These verses present a careful, lived experiment in wisdom. The speaker deliberately sets his mind to “know” and to “see” what is going on in human life, including the kind of relentless “business” that can erase normal rest (v.16). That investigation leads to a boundary: the “work of God” is real and active, but it is not something a human being can fully “find out” (v.17; repeated).
The text’s explicit claim is not that learning is worthless. It is that even intense effort and recognized expertise do not reach a complete explanation of what God is doing “under the sun.” The repeated use of “find out” (H4672) stresses the missing result: the search runs, but it cannot finish.
Where interpretation differs
What “business” refers to (v.16). Some take it mainly as outward labor and public affairs (the pressures of work, administration, commerce). Others think the emphasis is the inner effect of that activity—worry, mental churn, or anxious striving that keeps the eyes awake.
What “the work of God” includes (v.17). Some read it broadly as everything God is doing in the world (the whole pattern of events, outcomes, and timing). Others read it more narrowly as God’s hidden ordering of justice and outcomes in the kind of puzzling cases discussed earlier in the chapter.
How absolute “can’t find out” is. Some interpret the limit as total: humans cannot discover God’s full plan in principle. Others see a practical limit: humans can learn real truths, but not the whole map or final reasons behind events.
Why the disagreement exists
The passage uses general phrases (“business,” “work of God,” “under the sun”) without spelling out a single example. It also uses strong repetition (“won’t find it… won’t be able to find it”), which can sound either like an absolute statement about human limits or a forceful way of saying “not fully, not finally.”
What this passage clearly contributes
It adds a clear theme to Ecclesiastes’ larger argument: wisdom can observe much, but it cannot turn life into a fully solvable puzzle. God’s activity is the larger frame the speaker “sees,” yet it remains beyond complete human discovery. The text highlights a permanent mismatch between (1) human effort, experience, and reputation for insight and (2) the total explainability of reality “under the sun.” Ecclesiastes 8:16–8:17 makes that mismatch the conclusion of the speaker’s investigation.