(M278) A fresh and powerful argument in favour of the identity of the two festivals is furnished by the connexion which has been traced between both of them and the Jewish feast of Purim.(822) There are good grounds for believing that Purim was unknown to the Jews until after the exile, and that they learned to observe it during their captivity in the East. The festival is first mentioned in the book of Esther, which by the majority of critics is assigned to the fourth or third century B.C.,(823) and which certainly cannot be older than the Persian period, since the scene of the narrative is laid in Susa at the court of a Persian king Ahasuerus, whose name appears to be the Hebrew equivalent of Xerxes. The next reference to Purim occurs in the second book of Maccabees, a work written probably about the beginning of our era.(824) Thus from the absence of all notice of Purim in the older books of the Bible, we may fairly conclude that the festival was instituted or imported at a comparatively late date among the Jews. The same conclusion is supported by the book of Esther itself, which was manifestly written to explain the origin of the feast and to suggest motives for its observance. For, according to the author of the book, the festival was established to commemorate the deliverance of the Jews from a great danger which threatened them in Persia under the reign of King Xerxes. Thus the opinion of modern scholars that the feast of Purim, as celebrated by the Jews, was of late date and oriental origin, is borne out by the tradition of the Jews themselves. An examination of that tradition and the mode of celebrating the feast renders it probable that Purim is nothing but a more or less disguised form of the Babylonian festival of the Sacaea or Zakmuk.