Both Revised Standard Version and Good News Bible have a paragraph break here, which we recommend.

Menelaus also joined them and with utter hypocrisy urged Antiochus on, not for the sake of his country’s welfare, but because he thought that he would be established in office: Even though Menelaus was the Jewish High Priest (see 2Macc 4.23-24), he encouraged Antiochus to lead an army against his own people. It is not exactly clear what is meant by Menelaus also joined them, but since the next verse says the king ordered Menelaus to be taken to Beroea, we may assume that Menelaus did not join Antiochus and Lysias on the journey, but began the trip with them. Revised English Bible expresses this clause well with “Menelaus, who had also joined them.” With utter hypocrisy means Menelaus was acting and speaking in an insincere way, seeking only to advance his own interests. This phrase can be translated several ways; for example, “most disingenuously” (New English Bible), “with great duplicity” (New American Bible), “thoroughly concealing his real motives” (Goldstein), “very craftily” (New Jerusalem Bible), “with loud pretenses” (An American Translation), and “trying to take advantage of the situation” (Good News Bible). Since Menelaus was already the High Priest, he thought that he would be established in office cannot mean that he was seeking the office, only that he hoped to keep it. An alternative model for this verse is:

• Menelaus had joined them, and was doing everything he could to stay in the king’s favor. So he encouraged Antiochus in his plans. He cared nothing about the good of his own country [or, people]. He only wanted to be sure he could remain High Priest.

Quoted with permission from Bullard, Roger A. and Hatton, Howard A. A Handbook on 1-2 Maccabees. (UBS Helps for Translators). New York: UBS, 2011. For this and other handbooks for translators see here.