Ghosts, like any character in a book, need a motive – a reason for haunting. They don’t just turn up because there’s a vacant slot at the moated grange, or because the grey lady at the old rectory wants someone to make a fourth at bridge. They don’t attend night classes on the subject.
Usually, ghosts haunt because they’ve been cheated out of something. Or because they’ve been punished or even executed for a crime they didn’t commit. Or defrauded of an inheritance. Often they’re murder victims, of course.
The creation of ghosts is interesting. There are so many guises they can be given. They can be sad wailing shades 
who inhabit chilly ruins or cobweb-shrouded attics, or who drape themselves over stone fountains, and flit through tanglewood gardens. They can be murdered Tudor queens or spectral bridegrooms or walled-up nuns.
They can even be charming gentlemen in Elizabethan 
outfits, hinting slyly that they know where an undiscovered Shakespearean folio is buried.
But when I embarked on writing the second of Michael Flint and Nell West’s ghost exploits (the first was in Property of a Lady), I wanted a ghost who had a completely different set of motives.
I started by exploring the old religions. There’s a treasure house of material in ancient legends and lost rituals – except that not all of the rituals are lost. That search turned up the practice of sin-eating – an extraordinarily ancient custom. There are references to it as far 
back as the Old Testament and in some Aztec beliefs, but there are also much more recent traces of it. In Shropshire is the grave of a man called Richard Munslow, who died in 1906 and who is believed to have been the last known sin-eater in England.
In remote parts of the world, where an ordained priest couldn’t be brought to a dying person in time for a confession, the sin-eater would undertake the task. He – only rarely was it a ‘she’ – would be brought to the dying person’s bedside. There he would eat bread and drink water – wine if it could be provided – which had been placed on the breast of the dying one. It was believed that by this act the sin-eater removed the sins from the dying person, and took them onto his own soul. It’s perhaps not too much of a stretch to make a connection between the sin eater and the Jewish ‘scapegoat’ of the Old Testament.
The descriptions that exist of sin-eating rituals resemble each other strongly. The isolated hill farm or croft – the small, low-ceilinged room, smoky and dim from candle light and woodfires. The dying man or woman reciting the list of sins committed. And the sin eater absorbing the sins as he ate the symbolic meal. Afterwards he scurried off to find a priest to confess the catalogue of sins. If he couldn’t find a priest he might even go to another sin eater.
The 1911 Encyclopedia Britannica has this entry about sin eaters:
‘A symbolic survive of it (sin eating), was witnessed as recently as 1893 at Market Drayton, Shropshire.* After a preliminary service had been held over the coffin in the house, a woman poured out a glass of wine for each bearer, and handed it to him across the coffin with a “funeral biscuit”. In Upper Bavaria, sin-eating still survives: a corpse cake is placed on the breast of the dead and then eaten by the nearest relative, while in the Balkan peninsula a small bread image of the deceased is made and eaten by the survivors of the family. The Dutch doed-koecks or ‘dead cakes’, marked with the initials of the deceased, introduced into America in the 17th century, were long given to the attendants at funerals in old New York. The ‘burial cakes’ which are still made in parts of rural England, for example Lincolnshire and Cumberland, are almost certainly a relic of sin-eating.’
*This is possibly a reference to Richard Munslow of Shropshire.
One account I found of the sin-eater’s incantation is this:
‘I give easement and rest now to thee, dear man. Come not down the lanes or in our meadows. And for thy peace I pawn my own soul.’
I think it was that phrase, ‘I pawn my own soul’, that triggered the plot of the book. Supposing a sin eater took on a batch of sins – including the most mortal sin of all? Murder. And supposing that sin-eater died before he could offload the sins? Died – with his soul in pawn – believing he carried a murderer’s guilt? It seemed to me that if ever a ghost had a strong and slightly unusual motive for haunting, surely this was it.
And so the second book of the Michael Flint/Nell West series, The Sin Eater, came into being.
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