Genesis 38:10

Judah said to Onan, "Go in to your brother's wife, and perform the duty of a husband's brother to her, and raise up seed to your brother.

Onan knew that the seed wouldn't be his; and it happened, when he went in to his brother's wife, that he spilled it on the ground, lest he should give seed to his brother.

Then Judah said to Tamar, his daughter-in-law, "Remain a widow in your father's house, until Shelah, my son, is grown up;" for he said, "Lest he also die, like his brothers." Tamar went and lived in her father's house.

After many days, Shua's daughter, the wife of Judah, died. Judah was comforted, and went up to his sheepshearers to Timnah, he and his friend Hirah, the Adullamite.