Obadiah 1:3

"The pride of thy heart hath deceived thee, O thou that dwellest in the clefts of the rock, whose habitation is high; that saith in his heart, Who shall bring me down to the ground?"

This is a description of the national character of the Edomites, the traditional enemies of Israel, who were also their very close kinsmen, both being descended from the twin sons (Jacob and Esau) of Isaac, the Edomites being descended from Esau, and the Israelites from Jacob. The enmity between the two peoples dated from the patriarchal blessing which preferred Jacob above his brother, and from numerous encounters between the two peoples throughout their history.

"Thy pride hath deceived thee ..." The Edomites were justifiably proud of their fortress stronghold in the rocky vastness of Mount Seir, the rugged country south of Palestine and extending to the gulf of Aqabah. Their principal city was Petra, one of the most spectacular fortresses of the entire ancient world. Their great error was that of trusting in themselves instead of trusting in God. From the times of Jacob and Esau, their ancestor had been identified as "a fornicator and profane person" (Hebrews 12:16). It is a great mistake to suppose that God capriciously chose Jacob instead of Esau in the succession of the patriarchs, because it was definitely based upon the kind of man God knew each one to be. "Throughout the writings of the prophets Edom stands as a symbol of the earthly, non-spiritual people of the world."[2]

"Thou that dwellest in the clefts of the rocks ..." This is evidently a reference to the incredibly strong fortress of Petra, a whole city built in a narrow ravine of solid rock walls into which had been carved palaces, temples, dwellings, etc. A handful of men could have defended it against a whole army.