Voting for the successor of Pope John Paul II could begin as early as Monday evening, said Vatican Press Office director Joaquin Navarro-Valls.
The first conclave of the third millennium to elect the 265th Pope will open Monday afternoon with 115 cardinal electors from 52 countries and five continents.
The cardinals will move into their quarters at the 'Domus Sanctae Marthae' (House of St. Martha) Sunday afternoon.
On Monday, the first day of the conclave, a mass for the election of the Pope will be celebrated in St. Peter’s Basilica at 10 a.m. The cardinal electors will then process to the Sistine Chapel at 4:30 p.m. This will be the last ritual broadcast live on television.
"Once in the Sistine Chapel, all the cardinal electors will swear the oath,” explained Navarro-Valls. “The cardinal dean will read the formula of the oath, after which each cardinal, stating his name and placing his hand on the Gospel, will pronounce the words: 'I promise, pledge and swear.'”
After the oath, all those who do not participate in the conclave leave the Sistine Chapel. Only the master of Liturgical Celebrations and Tomas Cardinal Spidlik, who is above 80 years old, will remain for the meditation on the challenges facing the Church today. Once Cardinal Spidlik delivers the meditation, they, too, leave the chapel.
"As far as the first vote on Monday, the cardinals will decide whether or not to vote after they have entered into conclave on Monday afternoon,” said Navarro-Valls.
The cardinals will follow a tight and very structured schedule in the days that follow. Starting Tuesday, they will begin each day with a 7:30 a.m. mass at the House of St. Martha, followed by lauds at 9 a.m.
Morning voting will begin immediately at 9:30 a.m. The cardinals will return to the House of St. Martha at 12:15 p.m. and head back to the Sistine Chapel for voting at 4 p.m. The cardinals will pray the vespers at 7 p.m., before returning to their quarters at 7:20.
Voting period not indefinite
Each voting period can include up to two votes. After the two votes of the morning and the two of the afternoon respectively, the ballots and any notes the cardinals have made will be burned in a stove located inside the Sistine Chapel.
Smoke from the chapel’s chimney, indicating the result of the voting, could appear at around noon and at about 7 p.m., unless the new Pope is elected either in the first vote of the morning or the first vote of the afternoon, in which case the smoke signal will be earlier, explained Navarro-Valls.
If a new Pope is elected, the bells of St. Peter's will also ring.
The valid quorum for electing the Pope is two-thirds. After three days of voting without an election, there will be a day of reflection and prayer, without voting.
“Thereafter, voting will resume for seven additional ballots, another pause for reflection, another seven ballots, another pause and yet another seven ballots,” Navarro-Valls explained to reporters.
However, the process will not continue indefinitely. At the 33rd or 34th ballot, the cardinals will decide whether to proceed with an absolute majority vote or with balloting between two candidates, said Navarro-Valls.