Ecclesiastes 2:19

“And who knoweth whether he shall be a wise [man] or a fool? etc.] The king that should be after him, as the Targum, that should be his successor and heir; and so whether he would make a good or bad use of what was left; whether he would keep and improve it, or squander it away; suggesting, that could he be sure he would be a wise man that should come into his labours, it would be some satisfaction to him that he had laboured, and such a man should have the benefit of it; but as it was a precarious thing what he would be, he could take no pleasure in reviewing his labours he was about to leave. Some think that Solomon here gives a hint of the suspicion he had, that his son Rehoboam, his…”

“Solomon having found that wisdom and folly agree in being subject to vanity, now contrasts one with the other Ecclesiastes 2:13. Both are brought under vanity by events Ecclesiastes 2:14 which come on the wise man and the feel alike from without - death and oblivion Ecclesiastes 2:16, uncertainty Ecclesiastes 2:19, disappointment Ecclesiastes 2:21 - all happening by an external law beyond human control. Amidst this vanity, the good (see Ecclesiastes 2:10 note) that accrues to man, is the pleasure felt Ecclesiastes 2:24-26 in receiving God’s gifts, and in working with and for them. Ecclesiastes 2:12 What can the man do ... - i. e., “What is any man - in this study of wisdom and folly - after…”

“Or a fool - Who will undo all that I have done, and turn the effects of my wisdom into instruments of his folly. Some think he had such an opinion of Rehoboam. Ecclesiastes 2:20”

“2:19 Foolish, destructive successors are more of a threat to wise accomplishments than wise successors, but since the Teacher couldn’t tell what kind of successors he would have, his accomplishments were meaningless to him. Solomon’s immediate successor—his son Rehoboam—turned out to be foolish (see 1 Kgs 12:1-20).”

“who knoweth: Ecc 3:22; Kg1 12:14-20, Kg1 14:25-28; Ch2 10:13-16, Ch2 12:9, Ch2 12:10 wise under: Ecc 9:13; Luk 16:8; Jam 1:17, Jam 3:17 Ecclesiastes 2:20”

“"And who knoweth whether he shall be wise or foolish? and he will have power over all my labour with which had wearied myself, and had acted wisely, under the sun: this also is vain." או...ה, instead of אם...ה, in the double question, as at Job 16:3. What kind of a man he will be no one can previously know, and yet this person will have free control (cf. שׁלט, p.641) over all the labour that the testator has wisely gained by labour - a hendiadys, for חכם with the obj. accus. is only in such a connection possible: "my labour which I, acting wisely, gained by labour." In view of this doubtful future of that which was with pains and wisely gained by him, his spirit sank within him. Ecclesiastes…”