Today, July 3, is the feast day of Pope Saint Leo II (It used to be June 28). He succeeded another saint, Pope Agatho, in the Petrine office in the year 681 on January 10, although he was not consecrated for another nineteenth months. He died only ten months after his consecration. Leo was a peacemaker, keeping the Church free from the ecclesiastical interferences of the emperor in Constantinople and reconciling schismatic-minded bishops more loyal to Caesar than the See of Saint Peter. Pope Leo II and his predecessor both approved of the Third Ecumenical Council of Constantinople which, among other things, condemned the heresy of Monothelitism. This heresy was related to the Monophysite heresy which denied the full human nature in Christ — not the reality of the body, but the human soul and its two faculties of intellect and will. Without a human soul there is no human nature. The Monothelites accepted that Our Lord had a human intellect, but they denied that He had a human will. For them, and their champion, Patriarch Sergius I of Constantinople, there was only one “energy” in Christ.
The reason I find this pope and, Pope Agatho, so interesting is that they both condemned a previous pope, Honorius (625-638), for allowing the Monothelite heresy to flourish. Not only did these two popes approve the decrees of the Third Ecumenical Council, one of which condemned Honorius, for “failing to illuminate the Church with the apostolic doctrine,” and even more forcefully decreed: “Those whose impious dogmas we execrate, we judge that their names also shall be cast out of the holy Church of God”, that is, Sergius, Cyrus, Pyrrhus, Peter, Paul, Theodore, all which names were mentioned by the holy Pope Agatho in his letter to the pious and great emperor, “and were cast out by him, as holding views contrary to our orthodoxfaith; and these we define to be subject to anathema. And in addition to these we decide that Honorius also, who was pope of elder Rome, be with them cast out of the holy Church of God, and be anathematized with them, because we have found by his letter to Sergius that he followed his opinion in all things, and confirmed his wicked dogmas.” This decree was confirmed by Pope Agatho’s legates at the Council and then, after Agatho’s death, by Pope Saint Leo II himself.
Some Catholic scholars, perhaps the majority, have attempted to excuse Honorius of holding the heresy of Monothelitism, thereby taking issue with the finding of the fathers of Constantinople III. And I tend to believe they are right, for whatever that is worth. Honorius, to be sure, did condemn Monophysitism, but he refrained from condemning or approving of Sergius’ doctrine of “one will,” or “one energy.” So, on that score, the fathers of the Council of 680-81 may have been mistaken by confusing testimonies and documents. Remember, that even though this Council was approved by Popes Agatho and Leo II, its judgments on Honorius’ culpability were not definitions. Its decree condemning Monothelitism was, however, a definition of Faith — that decree was infallible, once the pope confirmed it. In any event, exculpating Pope Honorius from personal heresy in this matter has been difficult. The fact that the Church has tolerated the opinion of those who are convinced that he was himself guilty of not just allowing but defending Monothelitism goes to show that it is not against the Faith to hold that a pope could fall into heresy. What is against the Faith is to hold that a pope could teach heresy from the chair.
The Catholic Encyclopedia has a short article on Pope Saint Leo II here and a longer one here that is very informative on the controversy over Pope Honorius
