Tamar is yet another somewhat troubling parenthetical side story.

Awareness of some of the cultural expectations around marriage, descendants, and inheritance does help make sense of the story of Tamar, but it remains quite unusual to our culture-shifted ears. Tamar regains substantial agency in a fraught and powerless situation, and it seems she gives Judah a live-changing lesson. It is remarkable to observe how significantly Joseph and Judah both grow in character as they go on to feature in the closing (and climactic) stories of Genesis.