1. Judah's three sons and Tamar (1-11)

After Joseph was sold to Egypt, Judah might have been upset. He went out further from his brothers. He even married a Canaanite woman and had three sons. Er, his first son got married Tamar, but the Lord put him to death for his wickedness. Onan married her to keep the Levirate marriage law. But God put him to death too for not allowing Tamar to become pregnant. Judah was afraid of losing the third son too. So he sent Tamar to her parents pledging to give Shelah later.

2. Tamar bore Perez and Zerah (12-30)

When Judah did not keep his pledge, Tamar disguised herself and slept with Judah. It was to be faithful to her dead husband according to the law of God. God blessed her to become pregnant. Judah at first wanted to put her to death according to God's law. But he found she was more righteous than him. Thus, twin boys, Perez and Zerah were born. Tamar is the great grandmother of David. Perez is the ancestor of David and the Messiah, Jesus Christ. God kept his redemptive history through a faithful woman. God showed his mercy in the midst of the sinful natures of his chosen people.