Appian, Mithridatic Wars 16.106
Pompey then passed over Mount Taurus and made war against Antiochus, the king of Commagene, until the latter entered into friendly relations with him.
He also fought against Darius the Mede, and put him to flight, either because he had helped Antiochus, or Tigranes before him. He made war against the Arabs of Nabathæi, whose king was Aretas, and against the Jews (whose king, Aristobulus, had revolted), until he had captured their holiest city, Jerusalem. He advanced against, and brought under Roman rule without fighting, those parts of Cilicia that were not yet subject to it, and the remainder of Syria which lies along the Euphrates, and the countries called Cœle-Syria, Phœnicia, and Palestine, also Idumea and Ituræa, and the other parts of Syria by whatever name called; not that he had any complaint against Antiochus, the son of Antiochus Pius, who was present and asked for his paternal kingdom, but because he thought that since he (Pompey) had dispossessed Tigranes, the conqueror of Antiochus, it belonged to the Romans by the law of war. While he was settling these affairs ambassadors came to him from Phraates and Tigranes, who had gone to war with each other. Those of ligranes asked the aid of Pompey as an ally, while those of the Parthian sought to secure for him the friendship of the Roman people. As Pompey did not think it best to fight the Parthians without a decree of the Senate, he sent mediators to compose their differences.