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Huius pestis initia talia perferuntur. nam dum novitius in ea quisquam recipitur, et perditorum primitus scholas intrat, apparet ei species quaedam ranae, quam bufonem consueverunt aliqui nominare. hanc quidam a posterioribus et quidam in ore damnabiliter osculantes, linguam bestiae intra ora sua recipiunt et salivam. haec apparet interdum indebita quantitate, et quandoque in modum anseris vel anatis; plerumque furni etiam quantitatem assumit. demum novitio procedenti occurrit miri palloris homo, nigerrimos habens oculos, adeo extenuatus et macer, quod consumptis carnibus sola cutis relicta videtur ossibus superducta; hunc novitius osculatur, et sentit frigidum sicut glaciem, et post osculum catholicae fidei memoria de ipsius corde totaliter evanescit.
(Gregory IX, Vox in Rama)
The following rites of this pestilence are carried out: when any novice is to be received among them and enters the sect of the damned for the first time, the shape of a certain frog appears to him, the type that is usually called a toad. Some kiss this creature despicably on the hind quarters and some on the mouth, and they receive the tongue and saliva of the beast inside their mouths. Sometimes it appears unduly large, and sometimes equivalent to a goose or a duck; often it even assumes the size of an oven. At length, when the novice has come forward, he is met by a man of wondrous pallor, who has the blackest eyes and is so emaciated and thin that, since his flesh has been wasted, only his skin seems remain, drawn over his bones. The novice kisses him and feels cold like ice, and after the kiss the memory of the Catholic faith totally disappears from his heart. (tr. Alex October1625, adapted by David Bauwens)