institution and of its central role within the Catholic Church. Jesus's statement to Simon Peter, "whatever you bind on earth shall be bound in heaven, and whatever you loose on earth shall be loosed in heaven", is understood in Roman Catholic theology as establishing two jurisdictions, Heaven and Earth; the silver and gold keys are said to represent these two jurisdictions. The silver key symbolises the power to bind and loose on Earth, and the gold key the power to bind and loose in Heaven (another interpretation says that the silver key represents "binding" and the golden key represents "loosing"). The primary emblem of the papacy is these two keys beneath a triregnum (papal tiara). This symbol is used in several instances. The Pope's personal arms are surmounted by the aforementioned two keys in saltire behind the escutcheon (one key silver and one key gold, tied with a red cord), and above them the silver triregnum bearing three gold crowns and red infulae (the lappets which hang down from the back of the tiara and fall over the shoulders when it is worn). This tradition goes back to the 15th century, the symbolism of the keys of Peter was first used by Pope Nicholas V (elected 1447). The latest two popes (as of 2013; Benedict XVI and Pope Francis) have replaced the tiara with a simple mitre on which is depicted the three tiered cross of the papacy, reminiscent of the three tiers of the tiara. A listing of the coats of arms of the popes can be found at: papal coats of arms. The yellow and white flag of Vatican City also makes use of this emblem on the right hand side in the white half of the flag. The yellow and white colours were first adopted in 1808 as the flag of the personal guard of Pius VII, when the other forces of what had been the Papal States were brought under Napoleon's control. The previous flag was red and gold, the traditional colours of the city of Rome. The 1808 flag was of course not that of Vatican City, which did not come into existence until 1929. The coat of arms of the Holy See and that of Vatican City also use this papal emblem. The arms of the Holy See are blazoned: gules, two keys in saltire or and argent, interlacing in the rings or, beneath