39 Heb “man.” The term is used here in a generic sense and translated “no one.”
40 Heb “time.” 773 עֵת 2.d suggests that עֵת (’et, “time”) refers to an “uncertain time.” On the other hand, עֵת 6 nuances it as “destined time,” that is, “no one knows his destined time [i.e., hour of destiny].” It is used in parallelism with זְמָן (zéman, “appointed time; appointed hour”) in 3:1 ( זְמָן; 273 זְמָן). Eccl 3:9–15 teaches God’s sovereignty over the appointed time-table of human events. Similarly, Qoheleth here notes that no one knows what God has appointed in any situation or time. This highlights the limitations of human wisdom and human ability, as 9:11 stresses.
41 Heb “bad, evil.” The moral connotation hardly fits here. The adjective would seem to indicate that the net is the instrument whereby the fish come to ruin.
42 Heb “the sons of man.”
43 The Masoretes pointed the consonantal form יוקשׁים (“are ensnared”) as יוּקָשִׁים (yuqashim, Pual participle mpl from ַָיקֹשׁ, yaqosh, “to be ensnared”). This is an unusual form for a Pual participle: (1) The characteristic doubling of the middle consonant was omitted due to the lengthening of the preceding short vowel from יֻקָּשִׁים to יוּקָשִׁים ( §20.n and §52.s), and (2) The characteristic prefix םְ (mem) is absent, as in a few other Pual participles, e.g., Exod 3:2; Judg 13:8; 2 Kgs 2:10; Isa 30:24; 54:11 ( §52.s). On the other hand, the consonant form יוקשים might actually be an example of the old Qal passive participle which dropped out of Hebrew at an early stage, and was frequently mistaken by the Masoretes as a Pual form (e.g., Jer 13:10; 23:32) ( §52.s). Similarly, the Masoretes pointed אכל as אֻכָּל (’ukkal, Pual perfect 3rd person masculine singular “he was eaten”); however, it probably should be pointed אֻכַל (’ukhal, old Qal passive perfect 3rd person masculine singular “he was eaten”) because אָכַל (’akhal) only occurs in the Qal (see §22.6a).
44 Heb “evil.” The term רָעָה (ra’ah, “evil; unfortunate”) is repeated in v. 12 in the two parts of the comparison: “fish are caught in an evil (רָעָה) net” and “men are ensnared at an unfortunate (רָעָה) time.”

In other versions

ESVEnglish Standard Version

For man does not know his time. Like fish that are taken in an evil net, and like birds that are caught in a snare, so the children of man are snared at an evil time, when it suddenly falls upon them.

NIVNew International Version (2011)

Moreover, no one knows when their hour will come:

As fish are caught in a cruel net,

or birds are taken in a snare,

so people are trapped by evil times

that fall unexpectedly upon them.

CSBChristian Standard Bible

For certainly no one knows his time: like fish caught in a cruel net or like birds caught in a trap, so people are trapped in an evil time as it suddenly falls on them.

NLTNew Living Translation

People can never predict when hard times might come. Like fish in a net or birds in a trap, people are caught by sudden tragedy.

LEBThe Lexham English Bible

For man does not know his time. Just as fish are caught in a cruel net and like birds who are seized in a snare, so also humans are ensnared at a cruel time when it falls suddenly upon them.

KJV 1900King James Version

For man also knoweth not his time: as the fishes that are taken in an evil net, and as the birds that are caught in the snare; so are the sons of men snared in an evil time, when it falleth suddenly upon them.

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