To destroy witchcraft and all other diabolical and haunting influences;. As early as the 11th century, it may have initially had the form of Saint Benedict's cross, and was used by pope Leo IX. On the back is a poisoned cup, in reference to the legend of Benedict, which explains that hostile monks attempted to poison him: the cup containing poisoned wine shattered when the saint made the sign of the cross over it (and a raven carried away a poisoned loaf of bread).
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