Against Apion is a polemical work written by Flavius Josephus as a defense of Judaism as a classical religion and philosophy against criticism by Apion, stressing its antiquity against what he perceived as more recent traditions of the Greeks. One of his main sources was Menander of Ephesus. Against Apion cites Josephus' earlier work Antiquities of the Jews, so can be dated after C.E. 94. It was most likely written in the early second century.