Ecclesiastes 2:19; Ecclesiastes 11:6

Ecclesiastes 2:19

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.

Ecclesiastes 11:6

6 Sow your seed in the morning and do not be idle in the evening, for you do not know whether morning or evening sowing will succeed, or whether both of them alike will be good.