Story here.
The word is "incredulity".
How fitting an English tabloid can't spell it, since the English word is derived directly from the Latin "incredulus" for "not believing".
The cardinals in assembly, many of whom understood no Latin themselves, didn't understand what was happening:
"He announced his resignation in Latin to a meeting of Vatican cardinals this morning, saying he did not have the 'strength of mind and body' to continue leading more than a billion Roman Catholics worldwide. ... Several cardinals did not even understand what Benedict had said during the consistory, said the Reverend Federico Lombardi, the Vatican spokesman.
"Others who did were stunned.
"A cardinal who was at the meeting said: ‘We listened with a sense of incredulity as His Holiness told us of his decision to step down from the church that he so loves.’"
Well, there you go. A Pope "steps down from the church".
Dare we say, "Welcome, sir"?