Ecclesiastes 2:20

2:20 Therefore I went about to cause my heart to despair of all the labour which I took under the sun.

Ecclesiastes 4:4

4:4 Again, I considered all travail, and every right work, that for this a man is envied of his neighbour. This [is] also vanity and vexation of spirit.

Ecclesiastes 4:16

4:16 [There is] no end of all the people, [even] of all that have been before them: they also that come after shall not rejoice in him. Surely this also [is] vanity and vexation of spirit.

Ecclesiastes 5:12

5:12 The sleep of a labouring man [is] sweet, whether he eat little or much: but the abundance of the rich will not suffer him to sleep.

Ecclesiastes 8:12

8:12 Though a sinner do evil an hundred times, and his [days] be prolonged, yet surely I know that it shall be well with them that fear God, which fear before him: