The great central act of Christian worship is the Mass, a Sacrifice which can be offered to God alone, and the climax of the sabbat orgies is the horror of the black mass, a sacrifice of mockery, impiety, and blasphemy which is offered to the Devil. Satanists today often meet with the celebration of the black mass as their main object, and it is indeed the culmination and to use a term of the schools the very quiddity of devil-worship and the cult of hell. In detail the black mass imitates, so to speak and foully parodies with every circumstance of crapulous obscenity and contempt the Sacrifice of Calvary. The black mass today is sometimes celebrated in a cellar, but Satanists have become so audacious and so strong in evil that the largest room in their houses is known to be permanently fitted up for these abominable mysteries. In one case the room is draped with black hangings and the windows are always shuttered with curtains drawn.