the Catholic Church says that Jesus promised to protect the Church from doctrinal and moral error.  One expression of that protection is how the Pope cannot err under certain circumstances.

Pope Honorius is used as proof of papal fallibility for he allegedly taught the Monothelite heresy in his letter to Sergius, who was Patriarch of Constantinople. This doctrine said that Jesus had just one will while Catholic doctrine said that Jesus had two, a human and a divine will. Sergius subscribed to the heresy.  The heresy is major for it undermines the deity of Jesus and his full humanity.  For Christians getting Jesus right matters more than love!  When you look into the matter carefully you will see there is more than allegedly teaching heresy here.  He did it.
Honorius wrote a letter to Sergius which still exists. A second letter exists but only in fragments (page 30, The Church in the Christian Roman Empire, Studies in Comparative Religion, Rev Phillip Hughes, Catholic Truth Society, London, 1964).
Catholics use one of these lies to cover up the fact that Honorius is proof that papal infallibility is one of Rome’s many untruths.
# Lie One, Honorius was orthodox but just wrote ambiguously. He was misunderstood (page 159, Pope Fiction).
They say Honorius wrote in such a way that it could have been understood in an orthodox or Monothelite way which gave rise to the accusation of heresy. Monothelites said that Jesus had one will. But a person believing he has two can say that he has one in the sense that the two wills are in union and are one. Pope Fiction says that Sergius was a Monothelite. It says that Honorius was ambiguous and condemned the idea that there are two operations or wills in Christ. But it fobs us off by saying that he meant to condemn the idea of two wills in Christ going against one another. Then why didn’t he write that? Why write that he condemned the two wills? He knew he could write two contrary wills and would have done that had he meant that. The pope condemned the idea of one operation or will in Christ as well but he agreed with it. The reason he condemned the one and two will ideas was because he was declaring the issue unimportant and something people could make up their minds about. This is heresy for the Church says it is important to have the right doctrine to safeguard the divinity and full humanity of Jesus Christ.
The pope knew that ambiguity in papal bulls had to be avoided at all costs. He meant what he wrote.
Some would say that if Honorius was a heretic we cannot prove it and if he failed to condemn the heresy of Sergius that was a human error based on his misunderstanding and lack of proper information. They tell us that the doctrine of infallibility says that the pope is only infallible when he knows what he is doing unlike Honorius. But if you write a letter to a heretic in which you seem to agree with him and you with all the help you have at hand and you write more than one letter in which you do the same thing it is obvious the Catholics who say we cannot prove anything are lying. The letters were written to express the truth according to Honorius and when he didn’t do that he obviously agreed with Sergius.
Pope Fiction admits that Honorius forbade the doctrine that Jesus had two wills which is the accepted doctrine of the Christian faith but adds that he forbade the one will doctrine as well (page 161). So it confesses that he forbade the orthodox doctrine that Jesus had two wills. The pope was only saying then that it shouldn’t be discussed. So Pope Fiction says then that his sin was not in teaching heresy but in refusing to settle the dispute.
So if Pope Fiction is right, he made a dogma that either of the two doctrines was acceptable. This is a fact that the book refuses to face.
Honorius freely refused to condemn the one will doctrine though he could have. This tells us a lot. Though he refused to settle the dispute it is clear that he agreed that Jesus had only one will.

The problem with the view that the pope was just being unclear indicates that if he intended to inform the whole Church and be infallible then he was saying the matter was a mystery or uncertainty and that this mystery was a doctrine to be held by all the faithful.  A pope can surely infallibly proclaim a matter to be a mystery or uncertainty!  For example, Catholicism is riddled with mysteries.
# Lie Two, Honorius was not writing as pope but as a private theologian so he was not infallible but erred. Catholics teach that the pope can sin and make mistakes but cannot err when he uses his infallibility which Honorius was not using. The pope can err as a private theologian. Pope Fiction page 162 however admits that his letter was official. He was trying to answer a query for Sergius and his part of the Church which was a big part for the Constantinople Patriarch was a major leader in the Church. He was not teaching as a private theologian.

The Church says that Honorius just thought it didn’t matter if Jesus had one will or two. “And Honorius, so far from pronouncing an infallible opinion in the Monothelite controversy, was ‘quite extraordinarily not’ (as Gore used to say) pronouncing a decision at all. To the best of his human wisdom, he thought the controversy ought to be left unsettled, for the greater peace of the Church. In fact, he was an inopportunist. We, wise after the event, say that he was wrong. But nobody, I think, has ever claimed that the Pope is infallible in not defining a doctrine” (Difficulties, page 126-7). But in fact Honorius was making a dogma of the doctrine that we can believe that Jesus had one will or the orthodox doctrine that he had two. He proclaimed this to the whole Church for in his letter he told Sergius but this is heresy too. Honorius ignored those who wrote to him trying to correct him and in response to them he called his dogma a dogma of the Church meaning an infallible teaching to be accepted by the whole Church and addressed to the whole Church so again papal infallibility is refuted (page 196, A Handbook on the Papacy).

Honorius used the words, “We confess,” which means the Church and faith he is speaking for and himself meaning the right Church were declaring these things about Jesus that he had one will. He did make a decision and it agreed with that of Sergius. He agreed with the heresy of Sergius.
Honorius was posthumously condemned by the Sixth General Council which took place in Constantinople in 681 AD. In its Acts of the Thirteenth Session, it condemned his letters to Sergius as harmful to the soul. The letters were official statements of doctrine and meant to steer the Church towards the Monothelite heresy when they got that huge amount of attention. Why worry much about the statements of a private theologian or a dead Church leader or a few personal letters? Only very serious and authoritative documents could get such treatment. His letters were burned at the Session. At Session 16, the Council declared “ Accursed to the extreme be that heretic Honorius.” The Church found him guilty of heresy in his letters and excommunicated and cursed him.

Pope Leo 2 brought out a statement that the Council was right about Honorius and he too excommunicated and cursed him. Leo invoked the anathema against Honorius which is always a statement against heretics. It is a blatant lie that Leo interpreted the Council as not accusing Honorius as a Monothelite but as a person who wouldn’t do anything about the heresy. The lie is based on taking Leo’s words, “permitted her who is totally pure to be corrupted by polluted doctrine” to mean Leo condemned him for negligence and nothing else. But this wording could be used against somebody who taught explicit heresy too. Also if Honorius was simply negligent, he wasn’t the only pope who let heretics win the day and so why was he so severely attacked? Why was he singled out? Why did it matter so much though he was dead? Because he was an outward heretic not just a fence-sitter.
Leo wrote that he accepted the Sixth Session which condemned Honorius as a heretic. A heretical Church man to spread his heresy must first permit the heresy so the quote does not support the Catholic cause. Pope Leo II placed Honorius under the deepest excommunication of the Church the one that makes one “aeterna damnatione mulctati”. Leo accused Honorius of being a traitor who subverted the faith as did the Sixth Council of Constantinople (page 292, Vicars of Christ). 
The Council declared, “Having learned that the letters of Honorius are in total disagreement with the doctrines of the apostles and the definitions of the sacred councils and of all the fathers that are approved and that on the contrary they lean to the false teachings of the heretics we absolutely reject and condemn these letters. They are poison for the soul. We also state that Honorius who was once pope of the old Rome had also been rejected from God’s holy Church and is being accursed on account of the letters he sent to Sergius and in which he accepted Sergius’s beliefs in all things and reaffirmed his unholy doctrines”.
The Church today says that Leo II clarified this condemnation which was never approved by any pope (page 160, Pope Fiction) to say that Honorius was excommunicated and condemned for neglect not heresy. Leo is quoted as writing that Honorius didn’t do his job but fostered heresy by negligence (ibid page 160). But the Church is unable to quote anything that proves that Leo meant that when Honorius
The Church should agree with the original decree for it says ecumenical councils make binding decisions under the help of infallibility. Now would how could the Church have the right to excommunicate and condemn any dead pope for neglect? Would it do such a thing, of course not! Any pope can be accused of criminal neglect in many things. The Church is making out that Leo II was a lying rascal. Ecumenical councils and popes are infallible and here we have a pope denying that ecumenical councils are infallible and even correcting their decisions after they were made. Not even an infallible pope can have that right. The infallible cannot correct the infallible and if the Church isn’t infallible how can the pope be? If the council was right to excommunicate and condemn the pope as even Leo says though he denied Honorius was a heretic how can the pope really be the head of the Church and if the pope is not the head how can he be infallible? The popes then didn’t think they were the rocks the Church was built on and infallible. Nobody did.
Suppose Honorius was not expelled for heresy but for agreeing with Sergius, Patriarch of Constantinople, that the orthodox Christians and the heretics who believed that Jesus had only one will should stop quarrelling and get on with it. Catholics think this gets them off the hook because he did not define anything. But he defined that the Church can hold faith with heretics. It is not good enough to say that he was not declaring to the whole Church for he only wrote to Sergius. He was making a decision for the whole Church to embrace heretics as brothers for his decision makes no sense if it was not directed to the whole Church.  
Honorius made a decision to bind the Church and said it was the true faith so he was a true example of papal fallibility. He fulfilled all the conditions for making an infallible statement that were spelled out at Vatican 1 yet he was not infallible. The fact that the Church at the time of the Sixth Council did not descend into chaos and speculation that Honorius was a fake pope and a massive debate and schism from the papacy proves that papal infallibility was not recognised or believed in. If today’s pope used his infallibility to make Mary the incarnation of the Holy Spirit there would be a huge break from the Vatican and such a huge debate that everybody would be writing about it. There would be attempts to put the “true” pope in his place.
# Lie Three, Honorius didn't understand the dispute and thought it was not about how Jesus as God could have God's will and as man could have a separate human will but about what Jesus willed to do (page 30, The Church in the Christian Roman Empire, Studies in Comparative Religion, Rev Phillip Hughes, Catholic Truth Society, London, 1964). The pope said that when Jesus willed to do something the divine faculty of the will and the human faculty of the will agreed and so they were one will in the sense that they were the one intention. Thus he ended up being misunderstood and accused of saying Jesus didn't have a separate divine will faculty and a human will faculty but just had one faculty.
So the pope is said to have thought that the Lord Jesus had a divine will and a human will and the two wills were separate faculties but they were one will in the sense that they agreed together. The heretics were saying there was no separate human and divine will but only one will in Jesus as a faculty. All sides agreed that Jesus' divine side and human side were in agreement when he willed to do something.
There is no way the pope could have misunderstood such a simple point. His knowing that the heretics were not saying there was conflict of wills in Jesus when he did something proves that.

When Honorius was condemned as a heretic by the Church the condemnation never referred to his letters to Sergius as heresy or that he intended them to teach the Church. The Church makes out that this is important and shows there is no proof he really was a heretic. This is hair-splitting.

The outrage about the letters trying to teach the Church through Sergius a heresy was so big it did not need to be spelled out.  It is obvious that the condemnation of his heresy was about that.  The severity of the condemnation was remarkable and shows it was deemed necessary for Honorius abused his position to mislead the entire Church.

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