Ammon and Moab were happy about Judah's downfall, but Edom actively took part in it (see Ezekiel 35:5; Obadiah 1).
vengefully: The people of Edom captured those fleeing and handed over survivors to help the Babylonians (Obadiah 1:11–14). They were opportunists, settling old conflicts from the ancient feud between Jacob and Esau (Genesis 27:41). They took what they could from Judah’s suffering. In return, the Lord would destroy their land.