Genesis 38:30

Perez moved ahead of his brother, just like Joseph would soon do with his own brothers (chapters 39–47).

Judah’s family line continued through Tamar. The twins replaced Judah’s two sons who had died (38:7, 10). Their birth was similar to the birth of Jacob and Esau (25:21–26). As with Jacob and Esau, the expected order of birth was reversed. In both cases, the twin connected with the color red (scarlet) did not remain in the first place.

In a similar way, Jacob gained the right to rule over his older brother (27:29). This pattern seems to appear again in Judah’s family. The family line continued through Perez, not through the older son Shelah, whom Judah had tried hard to protect (38:11; see 1 Chronicles 4:21), and not through the older twin Zerah (see Ruth 4:13–22; Matthew 1:3).

The story of Judah and Tamar is a carefully placed break in the larger story. It shows what was happening in Judah’s family. Judah would later become an important leader. The story also shows the early stages of the family mixing with the people of the land. This helps explain why God sent the family to Egypt (chapters 39–47).

The Egyptians kept themselves separate from other peoples (43:32). Because of that, the Israelites were more likely to keep their own identity in Egypt than in Canaan.