Amos 1:11
Thus saith the LORD; For three transgressions of Edom, and for four, I will not turn away the punishment thereof; because he did pursue his brother with the sword, and did cast off all pity, and his anger did tear perpetually, and he kept his wrath for ever:
Amos's oracle against Edom stands as part of a wider series of divine warnings directed to the nations surrounding Israel. The charge is that Edom hunted down his kinsmen, the offspring of Jacob, with armed violence, stripped himself of all compassion, allowed his rage to rip without ceasing, and nursed his fury without end. The oracle makes plain that right dealing between human beings upholds the very fabric of society, and that nations will answer for the light and understanding entrusted to them, so that neglect of that trust invites retribution.
That retribution was not capricious but was fastened to Edom's own unrelenting harshness. By contrast, Jacob possessed no natural superiority over Esau, yet by trusting the divine promises he entered into sonship with God and shared heirship with Christ.