Abel is righteous, but ends up dead at the hand of his brother.

Jacob is perfect, and survives, in spite of Esau’s attempts to kill him.

That progression foretells the progression of Israel’s exiles. In Egypt, they are “Abel,” exalted at first but eventually enslaved and slaughtered by the Pharaoh who does not know Joseph. In Babylon, they are Jacob, surviving and often flourishing in spite of the hostility of their neighbors.

In Babylonian exile, Israel proves to be Israel, true sons of Jacob the wily.