(Verse 8, 9.) Shall I not in that day, saith the Lord, destroy the wise out of Edom, and understanding out of the mount of Esau? And thy mighty men shall be dismayed, O Teman, to the end that every one of the mount of Esau may be cut off by slaughter. Septuagint: In that day, saith the Lord, I will destroy the wise out of Edom, and understanding out of the mount of Esau. And thy mighty men, O Theman, shall be afraid, that every one from the mount of Esau may be cut off by destruction. When thy despoilers have seized thy borders, and all the men of thy league have mocked thee and have acquired strength against thee: then shall wisdom perish out of Edom and his subtlety shall be made foolishness. Moreover, the Lord will also take away prudence from Mount Esau, that is, from the mountains of Seir, either because the city of Idumea is situated on the mountain, or because all that region which borders on the south is desert, situated high on the mountains. Hence it is also said: Your warriors will be afraid, O Theman, which we interpret as the south. However, as I said above, Esau is called by three names: and likewise, the region of his kingdom, which borders on the south, is called by three names, Darom, Theman, Nageb, which all, according to Ezekiel, signify the south, the west, and the south. But when the strong men of his kingdom who dwelt in the South shall truly fear, then a man from the mountain of Esau, who both used to fight for the city and to wisely give counsel, shall perish. Otherwise: After those who were previously deceived have been converted to the Church, then, with the Lord Himself fighting, the wise men of Edom, who had a taste for worldly and earthly things, shall perish, and wisdom shall be taken away from the mountain of Esau, which was exalted against the knowledge of God. And those who previously fought for Esau and the dialectical art of Edom, and were in the garrisons of Teman, which means completion, will cease to fight for their former masters. Whether those who had promised themselves the light of knowledge and thought they were at noon, will fear and be afraid, with a scholarly man mastering their sophistries: to such an extent that no one will remain who is able to fight, either with the counsel of the king or with warrior men, against the pride and false teaching of the heretics.
[AD 420] Jerome on Obadiah 1:8-9