Persons hired at funerals in ancient times, to take upon themselves the sins of the deceased, that the soul might be delivered from purgatory.
“Notice was given to an old sire before the door of the house, when some of the family came out and furnished him with a cricket [low stool], on which he sat down facing the door; then they gave him a groat which he put in his pocket, a crust of bread which he ate, and a bowl of ale which he drank off at a draught. After this he got up from the cricket and pronounced ‘the ease and rest of the soul departed, for which he would yawn his own soul.’” —Bagford's letter on Leland's Collectanea, i. 76.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894