Esau

Esau is referenced here as the ancestor of Edom — invoking the ancient family rivalry between Jacob and Esau to underscore how Amaziah's defeat of Edom fit the long arc of Israelite history.

Esau is invoked here as the ancestral connection that explains why Edom exists — the nation they're recruiting as a third ally in the coalition descends from Jacob's brother Esau.

Esau is the ancestor referenced through Edom — the nation descended from him successfully revolted against Jehoram's Judah, reclaiming the independence that had been lost to the Davidic dynasty.

Esau's descendants occupy Mount Seir, and God explicitly tells Israel that this land belongs to them — their ancestor received it as a divine inheritance, placing it permanently off-limits to Israel.

Esau is referenced alongside Jacob as a casualty of family favoritism dynamics — his loss of the birthright illustrates the generational damage that follows when inheritance rights are distorted by preference.

Esau is cited as the ancestor of the Edomites, which is why Edomites receive more favorable treatment than Ammonites or Moabites — the family relationship with Jacob/Israel creates a different category of obligation.