This verse refers to Philopator’s tour of the area in 3 Macc 1.6-7.

And when we had granted very great revenues to the temples in the cities: Philopator describes how he made generous donations to all the temples in Greater Syria and Phoenicia. Contemporary English Version has a good model: “We even gave lots of money to honor their places of worship.” Another way to say this is “I even went to the cities of the area, and made generous gifts to the temples there.” The cities means all the cities except Jerusalem.

We came on to Jerusalem also, and went up to honor the temple of those wicked people: He was going to make a generous donation to the temple in Jerusalem also. Those wicked people may be translated as a separate clause by saying “But those people are wicked.”

Who never cease from their folly may be expressed as “there is no end to their foolishness” or “they never stop being foolish.”

Here is an alternative model for this verse:

• I went to the cities of the area, and made generous gifts to the temples there. Then I went to Jerusalem, intending to do the same to the temple there. But those people are wicked; there is no end to their foolishness [or, they never stop being foolish].

Quoted with permission from Bullard, Roger A. and Hatton, Howard A. A Handbook on 3-4 Maccabees. (UBS Helps for Translators). Miami: UBS, 2018. For this and other handbooks for translators see here.