Judaism does not condone vengeance on a personal level. It’s all right to wipe out entire nations that have done you wrong – the Midianites, the Philistines or Amalek for example – but vindictiveness towards other individual Jews is considered sinful. “You shall not take revenge,” the Book of Leviticus says emphatically, “and you shall not bear a grudge against the members of your people,” it then adds,…