Last Monday night and Tuesday were our Jewish festival of Purim, when we recall the events described in the Book of Esther. It is the oddest of all festivals. There is rejoicing, which starts a fortnight before at the beginning of the Jewish month of Adar. There’s a celebratory meal on the day itself. We send charitable gifts to the poor and presents to friends. There’s riotous noise during the reading of Esther whenever the name of the arch-villain Haman is mentioned. And it’s the one day in the year when it’s considered a religious duty to drink slightly too much alcohol. This might fit within the conventional parameters of rejoicing were it not for what the book of Esther records: the most drastic warrant for genocide in Jewish history, Haman’s plan ‘to destroy, kill and annihilate all the Jews — young and old, women and children — on a single day’.