With 135 cardinals eligible to vote, the coming conclave is set to be the largest in the history of the Catholic Church and one of the most unpredictable in decades.

Catholic cardinals on Monday set May 7 as the start date for the conclave to elect Pope Francis’ successor, delaying the secret voting for two days to help them get to know one another better and find consensus on a candidate before they are sequestered in the Sistine Chapel.

The date of the conclave was chief on the agenda of cardinals holding informal meetings to hash out church business following the April 21 death of Pope Francis. They held off on announcing the opening of the conclave until after his funeral on Saturday.