Genesis 4:8-15

8And Cain spoke to Abel his brother, and it came to pass when they were in the field, that Cain rose up against Abel his brother, and slew him.

9And Jehovah said to Cain, Where is Abel thy brother? And he said, I know not: am I my brother's keeper?

10And he said, What hast thou done? the voice of thy brother's blood is crying to me from the ground.

11And now be thou cursed from the ground, which hath opened its mouth to receive thy brother's blood from thy hand.

12When thou tillest the ground, it shall not henceforth yield thee its strength; a wanderer and fugitive shalt thou be on the earth.

13And Cain said to Jehovah, My punishment is too great to be borne.

14Behold, thou hast driven me this day from the face of the ground, and from thy face shall I be hid; and I shall be a wanderer and fugitive on the earth; and it will come to pass, [that] every one who finds me will slay me.

15And Jehovah said to him, Therefore, whoever slayeth Cain, it shall be revenged sevenfold. And Jehovah set a mark on Cain, lest any finding him should smite him.