In transforming an office with an aura of divinity into something far more human, Benedict’s decision has sent shock waves through the Vatican hierarchy, who next month will elect his successor. But it has also puzzled the faithful and scholars, who wonder how a pope can be infallible one day and fallible again the next — and whether that might undermine the authority of church teaching.

Benedict stunned the world last week when he said that he would retire on Feb. 28, a decision he said he had made “in full liberty and for the good of the church.” Even as the Vatican has tried to play down the confusion, saying that Canon Law provides for a clear transfer of power if a pope resigns, the implications of Benedict’s act remain unclear.

“What is the status of an ex-pope?” asked Ken Pennington, a professor of ecclesiastical and legal history at the Catholic University of America in Washington. “We have no rules about that at all. What is his title? What are his powers? Does he lose infallibility?”