The theme of reversal figures prominently in the traditional observance of Purim, which is seen as a kind of alter-ego to the solemn holiday of Yom Kippur, the Jewish Day of Atonement. In place of fasting there is feasting. In place of prayerful reflection there is revelry. In place of the simple white garments of purity there are costumes and spectacle.
Children especially look forward to dressing up on Purim. But Purim is in no way a Jewish Halloween. Just the opposite: children dress up and go door-to-door not to ask for treats and threaten tricks, but to give away gifts of food to others.
Which brings me to the point of this narrative, with only one more small digression.