Genesis 38:8, 11, 26

Then Judah said to Er’s brother Onan, “Your duty is to join yourself to her. Go perform your duty as a brother-in-law and provide an heir for your brother.”

Then Judah said to his daughter-in-law Tamar, “Live as a widow in your father’s house until my youngest son Shelah grows up.” So Tamar went home to her parents, but Judah worried that Shelah would end up dead like his brothers.

Judah recognized them as his and said, “She is more righteous than I, for I never gave my son Shelah to marry her.” And he let her go free and never slept with her again.