Sin eaters and the custom of sin eating seem to come from Wales. Early descriptions of the ritual all mention the bread eaten over the corpse, as well as the payment of sixpence to the person assuming the sins of the dead. Below are two 19th century accounts of sin eaters.
"In the county of Hereford was an old custom at funerals to hire poor people, who were to take upon them all the sins of the party deceased, and were called sin-eaters. One of them, I remember, lived in a cottage on Ross high-way. The manner was thus: when the corpse was brought out of the house, and laid on the bier, a loaf of bread was delivered to the sin-eater over the corpse, as also a mazar-bowl (a gossip's bowl of maple) full of beer, which he was to drink up, and sixpence in money; in consequence whereof, he took upon him, ipso facto, all the sins of the defunct, and freed him or her from walking after they were dead. In North Wales, the sin-eaters are frequently made use of; but there, instead of a bowl of beer, they have a bowl of milk. This custom was by some people observed, even in the strictest time of the Presbyterian government. And at Dyndar, volens nolens the parson of the parish, the relations of a woman deceased there had this ceremony punctually performed according to her will. The like was done in the city of Hereford in those times, where a woman kept many years before her death, a mazar bowl for the sin-eater, and in other places in this county, as also at Brecon, at Llangore, where Mr. Gwin, the minister, about 1640, could not hinder this superstition."
-- Aubrey of Gentilisme, MS. quoted in Kennett's Par. Ant. vol. 2, p. 276.
In some part of Wales a very extraordinary rite was observed. "When a person died, the friends sent for the sin-eater of the district, who on his arrival places a piece of salt on the breast of the defunct, and upon the salt a piece of bread. He then muttered an incantation over the bread, which he finally ate; thereby eating up all the sins of the deceased. This done, he received the fee of two shillings and sixpence, and vanished as quickly as possible from the general gaze; for as it was believed that he really appropriated to his own use and behoof the sins of all those over whom he performed the above ceremony, he was utterly detested in the neighbourhood -- regarded as a mere Pariah -- as one irremediably lost."
Sin-eating was not a Bardic idea, it seems to have been a perverted and perverse tradition, probably reaching Wales by an oriental channel, in which the Jewish scape-goat and Christian Eucharistic Sacrifice are blended in disguise and distortion. "The popular notion in Pembrokeshire, with reference to the placing of salt on the bodies of the dead, was that it kept away the evil spirit."
-- From Welsh sketches, by Ernest Silvanus Appleyard
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