8. Then Judah said to Er's brother Onan, “Go and sleep with your brother's widow. Fulfil your obligation to her as her husband's brother, so that your brother may have descendants.”
9. But Onan knew that the children would not belong to him, so whenever he had intercourse with his brother's widow, he let the semen spill on the ground, so that there would be no children for his brother.
10. What he did displeased the Lord, and the Lord killed him also.
11. Then Judah said to his daughter-in-law Tamar, “Return to your father's house and remain a widow until my son Shelah grows up.” He said this because he was afraid that Shelah would be killed, as his brothers had been. So Tamar went back home.