Catholic commentator Caroline Farrow has warned that cardinals participating in the papal conclave face "the most severe punishment the Church can impose" if they break their vow of secrecy.
The Vatican has taken extraordinary measures to ensure total secrecy, including sweeping the Sistine Chapel for bugs and telecommunications devices.
The process to elect the 267th pope begins today with cardinals from 70 countries participating.
The day will begin with a mass in St Peter's Basilica at 10am, presided over by 91-year-old Cardinal Dean Giovanni Battista Re.
The process to elect the 267th pope begins today
GB NEWS
Speaking about the top secret process, the commentator explained to GB News: "It's very exciting and it is extremely secretive.
"In fact, they've been sweeping the Sistine Chapel to ensure there are no bugs or telecommunications devices. All the cardinals who will take part in the conclave must take a very solemn oath a vow of secrecy that they will not share anything that is discussed.
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"Breaking that vow of secrecy carries the penalty of excommunication, which is the most severe punishment the Church can impose.
"That's the first step in the process. Around four o clock Vatican time the cardinals will process into the chapel. Then the Dean of the College of Cardinals will say extra omnes, which means everyone out. The doors will be sealed.
"I don't know if you know this, but the word conclave comes from Latin. Con" means with, and clavis means key so it means locked in with a key."
"They will then begin voting. It's likely to be black smoke, since it's very unlikely they will reach unanimity on a candidate this evening.
"Voting will begin in earnest tomorrow, with four rounds of voting each day two in the morning and two in the afternoon until a new pope is chosen."
For the past century, it has taken between three and eight ballots to find a pope.
John Paul I was elected on the third ballot, while John Paul II needed eight. Pope Francis was elected on the fifth ballot in 2013.
If no winner emerges, cardinals return to the Casa Santa Marta guesthouse for dinner, where crucial conversations take place.
The process to elect the 267th pope begins today
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Several challenges await the new pope, including whether to continue Francis' progressive legacy on women, LGBTQ+ acceptance, the environment and migrants.
The clergy sex abuse scandal also hung over pre-conclave discussions.
With Francis having appointed 80 per cent of the voting cardinals, continuity seems likely, though its exact form remains uncertain.
Outside the Sistine Chapel, thousands of faithful await the white smoke signalling a new pope.
