Ecclesiastes 11:7 (KJV)

Give a portion to seven, and also to eight; for thou knowest not what evil shall be upon the earth.

If the clouds be full of rain, they empty themselves upon the earth: and if the tree fall toward the south, or toward the north, in the place where the tree falleth, there it shall be.

He that observeth the wind shall not sow; and he that regardeth the clouds shall not reap.

As thou knowest not what is the way of the spirit, nor how the bones do grow in the womb of her that is with child: even so thou knowest not the works of God who maketh all.

In the morning sow thy seed, and in the evening withhold not thine hand: for thou knowest not whether shall prosper, either this or that, or whether they both shall be alike good.

But if a man live many years, and rejoice in them all; yet let him remember the days of darkness; for they shall be many. All that cometh is vanity.

Rejoice, O young man, in thy youth; and let thy heart cheer thee in the days of thy youth, and walk in the ways of thine heart, and in the sight of thine eyes: but know thou, that for all these things God will bring thee into judgment.

Therefore remove sorrow from thy heart, and put away evil from thy flesh: for childhood and youth are vanity.