While verses 5-6 focus on the ransacking of Edom's wealth, verses 7-8 home in on the diminution of their wisdom and understanding. In other words, their "smarts" will be taken from them. A parallel prophecy in Jeremiah 49:7 asks, "Is wisdom no more in Teman? Has counsel perished from the prudent? Has their wisdom vanished?"
These rhetorical questions presuppose that both counsel and wisdom are Edomite hallmarks. Historically, Edom was known in the region for its sagacity, having produced some notable wise men. In Job 1, the narrator relates that Job is from Uz, thought to have been in the area of Edom, and Job 4 introduces Eliphaz the Temanite, one of his (supposedly) wise friends who counseled him.
That Edom has a reputation for wisdom makes its removal a more personal, significant, and ghastly punishment. Indeed, it is a stern lesson for the reader: For their sins and crimes, the Edomites are prophesied to lose, not just their wealth, but also their less tangible riches—even their common sense! The worst part may be that they will fail to recognize that it has deserted them.
Verse 7 also describes their confederates and allies betraying them to the point that even Edom's ambassadors will be shown to the border, yet the Edomites will reckon that their "friends" are acting in good faith toward them. This is the essence of the last clause, "No one is aware of it," suggesting that none of the Edomites understands that they have been betrayed.
Obadiah paints an illustration of Edomites sitting down to eat with their allies and not perceiving the treacherous trap being laid for them. Something clouds or blinds their eyes. Similarly, the disciples on the road to Emmaus could not recognize Jesus, despite having spent many years with Him (Luke 24:16). One day, God will blind Edomite eyes to their peril just as He, for His own purposes, has blinded the minds of Israelites in the reading of His Word (II Corinthians 3:14-15). In Edom's case, He will remove her wisdom so that she will be unable to avoid betrayal and destruction.
Verse 9 relates the consequence of the loss of wisdom: Edomite leaders and warriors will lose their courage, leading to annihilation. Edom will reap what she has sown, which Obadiah details in the next section.
Richard T. Ritenbaugh
All About Edom (Part Five): Obadiah and God's Judgment