With the rise of the Chalcedonian Definition that stated Christ existed as one being with two natures and two corresponding wills, both human and divine, Orthodox Christology had become fairly well-established after the Council of Chalcedon, the fourth Ecumenical Council in Orthodox Christian history. However, with its rise also came the rise of separatist factions such as Nestorianism, which opposed the idea of Christ possessing any human qualities whatsoever, lest he be considered fallible and devoid of his divine nature. Other sects included Monophysitism and its branches such as monoenergism and monotheletism, which believed with variations that Christ existed as one man with two natures, in accordance with the Chalcedonian Definition, but also maintaining an energy or will of divine origin that superseded his human qualities. While the former Nestorianism had been denounced time and again through the Council of Chalcedon as well as the Second Council of Constantinople, With the Second Council, Emperor Justinian had attempted to strike a compromise with Monophysites to bring them back into the fold of Orthodox Christianity. For the most part, the compromise seemed to appease many through the Byzantine empire, although it upset the balance greatly in parts of northern Italy, who would not accept it in its entirely for almost a century and a half after the Second Council had concluded. This hostility carried until the rise of Constans II in AD 641. He saw the rift in opinion over the doctrine to be a threat to the empire’s stability, and he outlawed open conversation either for or against the doctrine simply for the sake of keeping the peace. By the time his son, Constantine IV, came to power and drove back the Muslims’ siege of Constantinople in AD 678, he was of the mind to make recompense with Rome over the doctrine. Between the Pope and the Emperor, bishops under their jurisdiction convened for the Third Council of Constantinople in AD 680.
The Council discussed matters almost exclusively pertaining to monoenergism and monotheletism, condemning them and branding them heretical as they went against the beliefs of Western tradition and the original Chalcedonian definition (elaborated upon in a letter from Pope Agatho), that Christ existed with two natures and two wills, both human divine with the human aspect being in subjection to the divine. The Council also branded Pope Honorius I, now long deceased at this point, as well as four previous patriarchs of Constantinople as heretical for supporting monoenergism and monotheletism. The schism between Constantinople and Rome seemed to have been rectified, as the decrees were reported back to Pope Leo II, the successor to Pope Agatho.
Pope Leo II would later write in support of the Council’s decision to brand Pope Honorius a heretic and to anathematize him posthumously. Pope Leo criticized Honorius of his silence while monotheletism too root around him and he allegedly did nothing to stop it or stem its flow, whether or not he actually shared in its beliefs.