KEY is also used for ecclesiastical jurisdiction; particularly for the power of excommunicating and absolving. The Romanists say, the pope has the power of the keys, and can open and shut paradise as he pleases; grounding their opinion on that expression of Jesus Christ to Peter, "I will give thee the keys of the kingdom of heaven." In St Gregory we read, that it was the custom heretofore for the popes to send a golden key to princes, wherein they enclosed a little of the filings of St Peter's chains kept with a world of devotion at Rome; and that these keys were worn in the bosom, as being supposed to contain some wonderful virtues.