In the Arab world, when one buys a house it is customary to purify it and ensure good luck by sacrificing a lamb. It is not uncommon to see the courtyard of a newly constructed house smeared with blood.

Before being sacrificed, the lamb should live in the new house for several days and come to feel at home there. The local butcher who performs the ritual should kill the animal with one motion so it feels no pain.

The lamb is eaten at an evening feast to which friends—but not neighbors—are invited. Once neighbors have been invited to your home, you are obligated forever after to offer them hospitality every time they knock.