” … Again, Gascon peasants believe that to revenge themselves on their enemies bad men will sometimes induce a priest to say a mass called the Mass of Saint Sécaire. Very few priests know this mass, and three-fourths of those who do know it would not say it for love or money. None but wicked priests dare to perform the gruesome ceremony, and you may be quite sure that they will have a very heavy account to render for it at the last day. No curate or bishop, not even the archbishop of Auch, can pardon them; that right belongs to the pope of Rome alone.
The Mass of Saint Sécaire may be said only in a ruined or deserted church, where owls mope and hoot, where bats flit in the gloaming, where gypsies lodge of nights, and where toads squat under the desecrated altar. Thither the bad priest comes by night with his light o’ love, and at the first stroke of eleven he begins to mumble the mass backwards, and ends just as the clocks are knelling the midnight hour. His leman acts as clerk. The host he blesses is black and has three points; he consecrates no wine, but instead he drinks the water of a well into which the body of an unbaptized infant has been flung. He makes the sign of the cross, but it is on the ground and with his left foot.
And many other things he does which no good Christian could look upon without being struck blind and deaf and dumb for the rest of his life. But the man for whom the mass is said withers away little by little, and nobody can say what is the matter with him; even the doctors can make nothing of it. They do not know that he is slowly dying of the Mass of Saint Sécaire.”