Genesis 38

Judah leaves his brothers and turns aside to an Adullamite named Hirah. He marries a Canaanite woman, Shuah's daughter, who bears him three sons: Er, Onan, and Shelah.

Judah takes Tamar as a wife for Er, but Er is evil in the eyes of Jehovah, and Jehovah causes him to die. Judah tells Onan to marry Er's widow and raise seed for his brother, but Onan refuses, spilling his semen on the ground, which is evil in God's eyes, and God causes him to die too.

Judah tells Tamar to remain a widow in her father's house until Shelah grows, fearing he might also die. After Judah's wife dies, Tamar hears he is going to Timnah to shear his sheep. She removes her widow's robes, covers herself with a veil, and disguises herself as a prostitute, sitting by the roadway. Judah, thinking her a prostitute, proposes to her, promising a kid from his flock. She demands a pledge: his signet ring, bracelet, and staff. He gives them to her, and she conceives by him.