AB, in the Hebrew chronology, the eleventh month of the civil year, and the fifth of the ecclesiastical year, which began with Nisan. This month answered to the moon of July, comprehending part of July and of August, and contained thirty days. The first day of this month is observed as a fast by the Jews, in memory of Aaron’s death; and the ninth, in commemoration of the destruction of the temple by Nebuchadnezzar, in the year before Christ 587. Josephus observes, that the burning of the temple by Nebuchadnezzar happened on the same day of the year on which it was afterward burned by Titus. The same day was remarkable for Adrian’s edict, which prohibited the Jews to continue in Judea, or to look toward Jerusalem and lament its desolation. The eighteenth day is also kept as a fast, because the sacred lamp was extinguished on that night, in the reign of Ahaz. On the twenty-first, or, according to Scaliger, the twenty-second day, was a feast called Xylophoria, from their laying up the necessary wood in the temple: and on the twenty-fourth, a feast in commemoration of the abolishing of a law by the Asmoneans, or Maccabees, which had been introduced by the Sadducees, and which enacted, that both sons and daughters should alike inherit the estate of their parents. ABADDON, Heb. corresponding to _Apollyon_, Gr. that is, _Destroyer_, is represented, Rev. ix, 11, as king of the locusts, and the angel of the bottomless pit. Le Clerc and Dr. Hammond understand by the locusts in this passage, the zealots and robbers who infested and desolated Judea before Jerusalem was taken by the Romans; and by Abaddon, John of Gischala, who having treacherously left that town before it was surrendered to Titus, came to Jerusalem and headed those of the zealots who acknowledged him as their king, and involved the Jews in many grievous calamities. The learned Grotius concurs in opinion, that the locusts are designed to represent the sect of the zealots, who appeared among the Jews during the siege, and at the time of the destruction of Jerusalem. But Mr. Mede remarks, that the title Abaddon alludes to Obodas, the common name of the ancient monarchs of that part of Arabia from which Mohammed came; and considers the passage as descriptive of the inundation of the Saracens. Mr. Lowman adopts and confirms this interpretation. He shows that the rise and progress of the Mohammedan religion and empire exhibit a signal accomplishment of this prophecy. All the circumstances here recited correspond to the character of the Arabians, and the history of the period that extended from A. D. 568 to A. D. 675. In conformity to this opinion, Abaddon may be understood to denote either Mohammed, who issued from the abyss, or the cave of Hera, to propagate his pretended revelations, or, more generally, the Saracen power. Mr. Bryant supposes Abaddon to have been the name of the Ophite deity, the worship of whom prevailed very anciently and very generally.