Why do Sedes not consider John XXIII a valid Pope?

[LausTibiChriste]

Sorry if this is a basic question, but I don't recall ever really hearing it addressed.

So why is John XXIII considered not a Pope by Sedes? Is it because he called the Council?

Sure he called it, but it was consummated after he died, so can he really be held responsible?

What error/heresy did he preach to cause him to lose the papacy?

[Kaesekopf]

IIRC, sedes say he taught heresy in Pacem in Terris or Mater et Magistra.

[Bonaventure]

IIRC, sedes say he taught heresy in Pacem in Terris or Mater et Magistra.

Correct

[Maximilian]

This whole article naming John XXIII as "Time Man of the Year" is well worth reading. The author was clearly on the inside and knew the score. His predictive ability is astounding, considering that we have the benefit of 60 years of hindsight, whereas he was writing soon after the convoking of the Council.

https://content.time.com/time/subscriber/printout/0,8816,829723,00.html

Pope John XXIII's New Pentecost
Friday, Jan. 04, 1963

That event was the beginning of a revolution in Christianity, the ancient faith whose 900 million adherents make it the world's largest religion.* It began on Oct. 11 in Rome and was the work of the man of the year. Pope John XXIII, who, by convening the Ecumenical Council called Vatican II, set in motion ideas and forces that will affect not merely Roman Catholics, not only Christians, but the whole world's ever expanding population long after Cuba is once again libre and India is free of attack.

So rare are councils—there have been only 20 in the nearly 2,000 years of Christian history—that merely by summoning Vatican II to "renew" the Roman Catholic Church Pope John made the biggest individual imprint on the year. But revolutions in Christianity are even rarer (the Reformation was 400 years ago), and John's historic mission is fired by a desire to endow the Christian faith with "a new Pentecost," a new spirit. It is aimed not only at bringing the mother church of Christendom into closer touch with the modern world, but at ending the division that has dissipated the Christian message for four centuries.

"The council may have an effect as profound as anything since the days of Martin Luther," says Dr. Carroll L. Shuster of Los Angeles, an executive of the Presbyterian Church. Boston University's Professor Edwin Booth, a Methodist and church historian, is so impressed by what Pope John has started that he ranks him as "one of the truly great Popes of Roman Catholic history."

Outranked Concerns. By launching singlehanded a revolution whose sweep and loftiness have caused it to outrank the secular concerns of the year, Pope John created history in a different dimension from that of the most dramatic head line of the year. President Kennedy's victory over the Russian missile threat in Cuba was both an embarrassing retreat for Khrushchev and a cold war turning point; it showed that a resolute U.S., willing to use its mighty arms, can maintain the initiative in the cold war.

[This is a very long article. I only posted the first couple paragraphs. You can use the link above to read the whole thing.]

[awkward customer]

So why is John XXIII considered not a Pope by Sedes? Is it because he called the Council?

Yes.

Sure he called it, but it was consummated after he died, so can he really be held responsible?

Yes.

What error/heresy did he preach to cause him to lose the papacy?

Modernism, which he caused to be manifested in the Church by the Council he called.

[Baylee]

I seem to recall that there are some sedevacantists who do not include Roncalli as one of the non-popes. I believe the reasoning is because he did not actually promulgate Vatican II.

[Baylee]

This whole article naming John XXIII as "Time Man of the Year" is well worth reading. The author was clearly on the inside and knew the score. His predictive ability is astounding, considering that we have the benefit of 60 years of hindsight, whereas he was writing soon after the convoking of the Council.

https://content.time.com/time/subscriber/printout/0,8816,829723,00.html

Pope John XXIII's New Pentecost
Friday, Jan. 04, 1963

That event was the beginning of a revolution in Christianity, the ancient faith whose 900 million adherents make it the world's largest religion.* It began on Oct. 11 in Rome and was the work of the man of the year. Pope John XXIII, who, by convening the Ecumenical Council called Vatican II, set in motion ideas and forces that will affect not merely Roman Catholics, not only Christians, but the whole world's ever expanding population long after Cuba is once again libre and India is free of attack.

So rare are councils—there have been only 20 in the nearly 2,000 years of Christian history—that merely by summoning Vatican II to "renew" the Roman Catholic Church Pope John made the biggest individual imprint on the year. But revolutions in Christianity are even rarer (the Reformation was 400 years ago), and John's historic mission is fired by a desire to endow the Christian faith with "a new Pentecost," a new spirit. It is aimed not only at bringing the mother church of Christendom into closer touch with the modern world, but at ending the division that has dissipated the Christian message for four centuries.

"The council may have an effect as profound as anything since the days of Martin Luther," says Dr. Carroll L. Shuster of Los Angeles, an executive of the Presbyterian Church. Boston University's Professor Edwin Booth, a Methodist and church historian, is so impressed by what Pope John has started that he ranks him as "one of the truly great Popes of Roman Catholic history."

Outranked Concerns. By launching singlehanded a revolution whose sweep and loftiness have caused it to outrank the secular concerns of the year, Pope John created history in a different dimension from that of the most dramatic head line of the year. President Kennedy's victory over the Russian missile threat in Cuba was both an embarrassing retreat for Khrushchev and a cold war turning point; it showed that a resolute U.S., willing to use its mighty arms, can maintain the initiative in the cold war.

[This is a very long article. I only posted the first couple paragraphs. You can use the link above to read the whole thing.]

A revolution.  A ....revolt.  Even the seculars got it.  Here we circle back to 2Thessalonians2.

[awkward customer]

This whole article naming John XXIII as "Time Man of the Year" is well worth reading. The author was clearly on the inside and knew the score. His predictive ability is astounding, considering that we have the benefit of 60 years of hindsight, whereas he was writing soon after the convoking of the Council.

https://content.time.com/time/subscriber/printout/0,8816,829723,00.html

Pope John XXIII's New Pentecost
Friday, Jan. 04, 1963

That event was the beginning of a revolution in Christianity, the ancient faith whose 900 million adherents make it the world's largest religion.* It began on Oct. 11 in Rome and was the work of the man of the year. Pope John XXIII, who, by convening the Ecumenical Council called Vatican II, set in motion ideas and forces that will affect not merely Roman Catholics, not only Christians, but the whole world's ever expanding population long after Cuba is once again libre and India is free of attack.

So rare are councils—there have been only 20 in the nearly 2,000 years of Christian history—that merely by summoning Vatican II to "renew" the Roman Catholic Church Pope John made the biggest individual imprint on the year. But revolutions in Christianity are even rarer (the Reformation was 400 years ago), and John's historic mission is fired by a desire to endow the Christian faith with "a new Pentecost," a new spirit. It is aimed not only at bringing the mother church of Christendom into closer touch with the modern world, but at ending the division that has dissipated the Christian message for four centuries.

"The council may have an effect as profound as anything since the days of Martin Luther," says Dr. Carroll L. Shuster of Los Angeles, an executive of the Presbyterian Church. Boston University's Professor Edwin Booth, a Methodist and church historian, is so impressed by what Pope John has started that he ranks him as "one of the truly great Popes of Roman Catholic history."

Outranked Concerns. By launching singlehanded a revolution whose sweep and loftiness have caused it to outrank the secular concerns of the year, Pope John created history in a different dimension from that of the most dramatic head line of the year. President Kennedy's victory over the Russian missile threat in Cuba was both an embarrassing retreat for Khrushchev and a cold war turning point; it showed that a resolute U.S., willing to use its mighty arms, can maintain the initiative in the cold war.

[This is a very long article. I only posted the first couple paragraphs. You can use the link above to read the whole thing.]

A revolution.  A ....revolt.  Even the seculars got it.  Here we circle back to 2Thessalonians2.

That's right.  They've already told us that Vatican II is the Revolt.

[Santantonio]

Not all sedes refer to the above as the only, or even primary reason J23 was not valid.

Others say it was the Siri Theory/White Smoke 1958/Pope in Red, which is enough to make one wonder
if the conclave was valid that elected him.

[Bataar]

Another reason some don't consider him to be valid include the evidence that he was a freemason before becoming pope. If this is true, he would not have been a Catholic and therefore his election would have been invalid.