While the first and second books of Maccabees are not part of the Hebrew Bible, they have been read by Jews as well as Christians over the ages, and have been the main source of the Jewish understanding of the Hanukkah story. Third Maccabees, by contrast, has been forgotten by both Jews and most Christians, although it is included in the Orthodox Christian canon. Written after 1 and 2 Maccabees, it tells the story of the prior persecution of the Jews by the 3rd-century-BCE Greek-Egyptian ruler Ptolemy IV Philopator, a few decades before the Maccabean revolt. Philip Long describes the book’s undeniably Jewish message:
Third Maccabees may have been written as a defense of Diaspora Jews for a Palestinian Jewish audience. Since these Jews live outside the land, they are considered to be “still in exile” and are therefore still under God’s [negative] judgment. The book demonstrates that God hears the prayers of the Diaspora Jewish community and preserves them in persecution, as he did for Palestinian Jewry during the time of Antiochus IV Epiphanes. It is possible the Jews in Jerusalem looked down on the Jews living outside the land. [The book’s message is that the] Jew of the Diaspora has as close of a connection to God as do the Jews living in the land.
The book [also] addresses the problem of apostasy in the Diaspora since those Jews in the book who renounce their faith are judged harshly. A major theme of the book is the boundary between the Jew and the Gentile. When Gentiles appear in the story, they are prejudiced, lawless, and abominable. Even in Egypt Jews are warned to keep their distance from Gentiles and to avoid apostasy at all cost.
Read more on Reading Acts: https://readingacts.com/2017/03/03/what-is-third-maccabees/