When the cardinals finally choose a prospective pope, the ballots will be burned without chemicals, producing a puff of white smoke.
After the potential new pope is selectedstill behind closed doorsthe dean of the College of Cardinals will ask the victor if he agrees to become the pontiff. When the new pope utters the word accepto, he will be asked to select a new name.
The tradition of taking new names dates to A.D. 533, when a priest named Mercury was selected. Wanting a more Catholic-sounding moniker, he changed his name to John.
The new pope will be outfitted in white vestments, several of which will have been made beforehand in various sizes. Then he will be allowed to greet the throngs awaiting his first appearance at St. Peter's Basilica's central window, where the pope traditionally gives his Easter blessing.
The World Changes; the Vatican Does Not
There is some historical precedent for the need for secrecy. In the papacy's early history political rulers and noble families tried to control the Catholic Church to further their own interests. At various times papal elections included laypeople and bishops and were subject to the approval of kings and queens.
The results read like a medieval soap opera. Popes were murdered, exiled, and threatened by nobility, and the papacy was often vacant for long periods while factions fought over it.
Conclave "started as a protection against governments that used to interfere with the voting and to preserve the freedom of the cardinals," noted Michael Fahey, a priest and professor of theology at Marquette University in Milwaukee, Wisconsin. "Now it is part of the ritual."
The current process of conclave was refined over time but reflects its turbulent past. In an effort to wrest control of the papacy from outside interests, Pope Nicholas II declared in 1059 that the cardinals had the exclusive right to elect a new pope.
In 1179 Pope Alexander III established that popes must be elected by a two-thirds majority.
Following the death of Pope Gregory IX in 1241, the cardinals, who were deeply divided, were locked in a palace until they reached a decision. This is where the term "conclave" comes fromit's a derivative of the Latin term cum clave, which means "with key."
It has been centuries since a German prince or Italian heiress plotted to take over the papacy. The Vatican, however, maintains that its secrecy ensures that the process doesn't become tainted.
Allen, the National Catholic Reporter correspodent, said the process is unlikely to change. "These rituals carry in them the history and the theology of the church," he said. "That is why even the small changes are met with controversy."
When Pope Paul VI did away with the papal throne, feeling it removed the pope from the people, he was criticized. And John Paul IInot known for shaking things updeclared that the cardinals can elect a pope by simple majority if, after 30 voting sessions, they are deeply deadlocked.
Should it come to that, Allen said, it will be controversial. "I think it is unlikely, because there is pressure not to appear divided," he said.
As much as it resists change, the Vatican adopted a truly modern change in 1975. Once the "everyone out" call is made, security experts sweep the Sistine Chapel for hidden listening devices. It's something of a no-change change, designed to maintain perhaps the conclave's greatest tradition of all: secrecy.
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