Genesis 38:9–12

9 But Onan knew that the offspring would not be his; so when he went in to his brother’s wife he spilled the semen on the ground, lest he should give offspring to his brother. 10 And what he did was displeasing in the sight of the Lord, and he slew him also. 11 Then Judah said to Tamar his daughter-in-law, “Remain a widow in your father’s house, till Shelah my son grows up”—for he feared that he would die, like his brothers. So Tamar went and dwelt in her father’s house.

12 In course of time the wife of Judah, Shua’s daughter, died; and when Judah was comforted, he went up to Timnah to his sheepshearers, he and his friend Hirah the Adullamite.