Church grim

[4] The English church grim usually takes the form of a large black dog with red eyes and guards churchyards from those who would profane them, including thieves, vandals, witches, warlocks, and the Devil himself.

In the 19th century, folklorists believed that it had once been the custom to bury a dog alive under the cornerstone of a church as a foundation sacrifice so that its ghost might serve as a guardian.

[2][3] Like many spectral black dogs, the grim, according to Yorkshire tradition, is also an ominous warning and is known to toll the church bell at midnight before a death takes place.

During funerals, the presiding clergy may see the grim looking out from the church tower and determine from its aspect whether the soul of the deceased is destined for Heaven or Hell.

[3][6] According to a related belief in Scotland, the spirit of the person most recently buried in a churchyard had to protect it until the next funeral provided a new guardian to replace them.

[12] It dwells in the church tower or some other place of concealment, wanders the grounds at night, and is tasked with protecting the sacred building.

When a person enters the church when services are not being held, he may see the lamb, and if it appears in the graveyard (especially to the gravedigger), then it portends the death of a child.

In this tale, Jack is helped by the ghost of a young woman who, like the church grim, was buried alive as a foundation sacrifice.