This also is a sore evil. The thought of Ecclesiastes 5:15 is emphatically repeated. In all points as he came; i.e. naked, helpless. And what profit hath he that laboreth for the wind? The answer is emphatically "nothing."
We have had similar questions in Ecclesiastes 1:3; Ecclesiastes 2:22; Ecclesiastes 3:9. To labor for the wind is to toil with no result, like the "feeding on wind, pursuing of vanity," which is the key-note of the book.
The wind is the type of all that is empty, delusive, unsubstantial. In Proverbs 11:29 we have the phrase, "to inherit the wind." Job calls futile arguments "words of wind" (Job 16:3; Job 15:2). Thus the Greek proverb ἀνέμους θρᾶν ἐν δικτύος to try to catch the wind:" and the Latin, "Ventos pascere," and "Ventos colere "(see Erasmus, 'Adag.
,' s.v. "Inanis opera"). Septuagint, καὶ τίς ἡ περίσσεια αὐτοῦ ᾖ μοχθεῖ εἰς ἄνεμον; "And what is his gain for which he labors for the wind?"