Is it possible for someone to be an antipope even though the majority of cardinals claim he is pope? The case of Antipope Anacletus II proves that it is possible for a majority of cardinals to claim a man is pope while he, in reality, is an antipope. In 1130, a majority of cardinals voted for Cardinal Peter Pierleone to be pope. He called himself Anacletus II. He was proclaimed pope and ruled Rome for eight years by vote and consent of a absolute majority of the cardinals despite the fact he was a antipope. In 1130, just prior to the election of antipope Anacletus, a small minority of cardinals elected the real pope: Pope Innocent II. How is this possible? St. Bernard said "the 'sanior pars' (the wiser portion)... declared in favor of Innocent II. By this he probably meant a majority of the cardinal-bishops." (St. Bernard of Clairvaux by Leon Christiani, Page 72) Again, how is this possible when the absolute majority of cardinals voted for A...

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Benedict XVI abdicated the ministry instead of the Munus Petrino, a requirement of the Universi Dominici Gregis for the legitimacy of the act according to canonical norm 32.2. Thus Ratzinger died remaining as legitimate Pope.
And that for a good understanding half a word is enough.
Divine providence has anticipated this to make clear in modern times in order to avoid this confusion of today.
St. Francis of Assisi prophesied a non-canonically elected pope would be the cause of great trials. And he says that the fault, in this canonical context presented by him, is that many prefer to consent, rather than fight this canonical error. Thus there would be diversity of opinions and schisms among Catholics. And he revealed that in those times if they were not abbreviated even the elect would be misled. His reasoning would demonstrate the lack of charity to the Church and its norms, which are related to the authority of a legitimate Vicar of Christ, that all this chaos would occur.
Knowing this, the saint of Assisi always obliged his friars to obey the Roman Pontiff, but a canonically legitimate Pope.
Because he knew that the Catholic Church is united to the legitimate Pope, and a legitimate Pope united to the Catholic Church.
It is up to everyone to discern in order to understand what is likely to happen soon.