Ecclesiastes 2:23 New English Translation

²³For all day long^[a] his work produces pain and frustration,^[b]
and even at night his mind cannot relax.^[c]
This also is futile!

Ecclesiastes 2:23 tn Heb “all his days.”
Ecclesiastes 2:23 tn The syntax of this verse has been interpreted in two different ways: (1) The phrase “all his days” (כָל־יָמָיו, khol yamayv) is the subject of a verbless clause, and the noun “pain” (מַכְאֹבִים, makhʾovim) is a predicate nominative or a predicate of apposition (see R. J. Williams, Hebrew Syntax, 15-16, §71). Likewise, the noun “his work” (עִנְיָנוֹ, ʿinyano) is the subject of a second verbless clause, and the vexation” (כַעַס, khaʿas) is a predicate nominative: “All his days are pain, and his work is vexation.” (2) The noun “his work” (עִנְיָנוֹ) is the subject of both nouns, “pain and vexation” (וָכַעַס מַכְאֹבִים, makhʾovim vakhaʿas), which are predicate nominatives, while the phrase “all his days” (כָל־יָמָיו) is an adverbial accusative functioning temporally: “All day long, his work is pain and vexation.” The latter option is supported by the parallelism between “even at night” and “all day long.” This verse draws out an ironic contrast/comparison between his physical toil/labor during the day and his emotional anxiety at night. Even at night, he has no break!
Ecclesiastes 2:23 tn Heb “his heart (i.e., mind) does not rest.”

New English Translation (NET)