Jason, as High Priest, scorning the traditional Jewish monotheism of the Pharisaic party, promotes Greek culture and religion throughout Judaea.
In return for a considerable sum, Antiochus has permitted Jason to build a gymnasium in Jerusalem and to introduce the Greek mode of educating young people.
Jason has reestablished Jerusalem as a Greek-style polis named after the king, Antioch-at-Jerusalem.
With the creation of Antioch, Jason has abandoned the ordinances given under Antiochus III, which defined the polity of the Judeans according to the Torah.
Jason's time as High Priest is brought to an abrupt end in 172 BCE when he sends Menelaus, the brother of Simon the Benjamite, to deliver the annual tribute money to Antiochus.
Although during the three years of his pontificate Jason has given many proofs of his attachment to the Hellenistic party, the zealous Hellenists of the stamp of the Tobiads, a Jewish or Ammonite faction, plot his overthrow, suspecting him of partiality to traditional Judaism.
Menelaus takes the opportunity to "outbid" Jason for the priesthood, resulting in Antiochus confirming Menelaus as the High Priest.
Jason flees Jerusalem and finds refuge in the land of the Ammonites, by which is probably meant the Nabataeans.
An officer named Sostrates is sent by Antiochus with a troop of Cyprian soldiers to subdue any opposition that might be attempted by the followers of the deposed Jason and to collect at the same time the sum Menelaus had promised.
Menelaus' first act is to seize the sacred vessels in the Temple stores in order to meet the obligations he has incurred.
This act comes to the ears of the deposed high priest Onias III, who publicly accuses Menelaus of robbing the Temple.
The latter, afraid of the consequences of this accusation, induces the king's lieutenant Andronicus, who had had his share of the plunder, to get rid of Onias before a formal complaint had been lodged with the king.
Accordingly, Onias is decoyed from the sanctuary at Daphne, in which he has sought refuge, and murdered.
Menelaus continues to plunder the treasures of the Temple until violence ensues, in which his brother Lysimachus meets his death.
He then brings before the king an accusation against the people of Jerusalem, that they are partisans of the Egyptians and persecute him only because he is opposed to their party intrigues.
This accusation causes the execution of several Jews who, although they had proved beyond any doubt that Menelaus and Lysimachus had desecrated the Temple, were sentenced to death.