Ecclesiastes 2:19; Ecclesiastes 2:25; Ecclesiastes 3:21-22; Ecclesiastes 4:8; Ecclesiastes 5:10; Ecclesiastes 6:12; Ecclesiastes 7:13; Ecclesiastes 7:24; Ecclesiastes 8:1; Ecclesiastes 8:4; Ecclesiastes 8:7; Ecclesiastes 9:4; Ecclesiastes 10:14

19 And who knows whether he will be a wise man or a fool? Yet he will have control over all the fruit of my labor for which I have labored by acting wisely under the sun. This too is vanity.
25 For who can eat and who can have enjoyment without Him?
21 Who knows that the breath of man ascends upward and the breath of the beast descends downward to the earth? 22 I have seen that nothing is better than that man should be happy in his activities, for that is his lot. For who will bring him to see what will occur after him?
8 There was a certain man without a dependent, having neither a son nor a brother, yet there was no end to all his labor. Indeed, his eyes were not satisfied with riches and he never asked, "And for whom am I laboring and depriving myself of pleasure?" This too is vanity and it is a grievous task.
10 He who loves money will not be satisfied with money, nor he who loves abundance with its income. This too is vanity.
12 For who knows what is good for a man during his lifetime, during the few years of his futile life? He will spend them like a shadow. For who can tell a man what will be after him under the sun?
13 Consider the work of God, For who is able to straighten what He has bent?
24 What has been is remote and exceedingly mysterious. Who can discover it?
1 Who is like the wise man and who knows the interpretation of a matter? A man's wisdom illumines him and causes his stern face to beam.
4 Since the word of the king is authoritative, who will say to him, "What are you doing?"
7 If no one knows what will happen, who can tell him when it will happen?
4 For whoever is joined with all the living, there is hope; surely a live dog is better than a dead lion.
14 Yet the fool multiplies words. No man knows what will happen, and who can tell him what will come after him?