Genesis 4:11-15

Now you are cursed from the ground, which has opened its mouth to receive your brother’s blood from your hand.

When you cultivate the ground, it will no longer yield its strength to you; you will be a wanderer and a drifter on the earth.”

Cain said to the Lord, “My punishment is too great to endure!

Behold, You have driven me this day from the face of the ground; and I will be hidden from Your face, and I will be a wanderer and a drifter on the earth, and whoever finds me will kill me.”

So the Lord said to him, “Therefore whoever kills Cain, vengeance will be taken on him seven times as much.” And the Lord placed a mark on Cain, so that no one finding him would kill him.