A Commentary, Critical, Practical, and Explanatory on the Old and New Testaments, by Robert Jamieson, A.R. Fausset and David Brown  at sacred-texts.com
oba 0:0This is the shortest book in the Old Testament. The name means "servant of Jehovah." Obadiah stands fourth among the minor prophets according to the Hebrew arrangement of the canon, the fifth according to the Greek. Some consider him to be the same as the Obadiah who superintended the restoration of the temple under Josiah, 627 B.C. (Ch2 34:12). But Oba 1:11-16, Oba 1:20 imply that Jerusalem was by this time overthrown by the Chaldeans, and that he refers to the cruelty of Edom towards the Jews on that occasion, which is referred to also in Lam 4:21-22; Eze 25:12-14; Eze 35:1-15; Psa 137:7. From comparing Oba 1:5 with Jer 49:9, Oba 1:6 with Jer 49:10, Oba 1:8 with Jer 49:7, it appears that Jeremiah embodied in his prophecies part of Obadiah's, as he had done in the case of other prophets also (compare Isa. 15:1-16:14 with Jer. 48:1-47). The reason for the present position of Obadiah before other of the minor prophets anterior in date is: Amos at the close of his prophecies foretells the subjugation of Edom hereafter by the Jews; the arranger of the minor prophets in one volume, therefore, placed Obadiah next, as being a fuller statement, and, as it were, a commentary on the foregoing briefer prophecy of Amos as to Edom [MAURER]. (Compare Amo 1:11). The date of Obadiah's prophecies was probably immediately after the taking of Jerusalem by Nebuchadnezzar, 588 B.C. Five years afterwards (583 B.C.). Edom was conquered by Nebuchadnezzar. Jeremiah must have incorporated part of Obadiah's prophecies with his own immediately after they were uttered, thus stamping his canonicity.
JEROME makes him contemporary with Hosea, Joel, and Amos. It is an argument in favor of this view that Jeremiah would be more likely to insert in his prophecies a portion from a preceding prophet than from a contemporary. If so, the allusion in Oba 1:11-14 will be to one of the former captures of Jerusalem: by the Egyptians under Rehoboam (Kg1 14:25-26; Ch2 12:2, &c.), or that by the Philistines and Arabians in the reign of Joram (Ch2 21:16-17); or that by Joash, king of Israel, in the reign of Amaziah (Ch2 25:22-23); or that in the reign of Jehoiakim (Kg2 24:1, &c.); or that in the reign of Jehoiachin (Kg2 24:8-16). On all occasions the Idumeans were hostile to the Jews; and the terms in which that enmity is characterized are not stronger in Obadiah than in Joe 3:19 (compare Oba 1:10; Amo 1:11-12). The probable capture of Jerusalem alluded to by Obadiah is that by Joash and the Israelites in the reign of Amaziah. For as, a little before, in the reign of the same Amaziah, the Jews had treated harshly the Edomites after conquering them in battle (Ch2 25:11-23), it is probable that the Edomites, in revenge, joined the Israelites in the attack on Jerusalem [JAEGER].
This book may be divided into two parts: (1) Oba 1:1-6 set forth Edom's violence toward his brother Israel in the day of the latter's distress, and his coming destruction with the rest of the foes of Judah; (2) Oba 1:17-21, the coming re-establishment of the Jews in their own possessions, to which shall be added those of the neighboring peoples, and especially those of Edom.