(24 Nov. 642–14 May 649)
A Greek, born at Jerusalem and son of a bishop, he had probably come to Rome as a refugee from the Arab invasions. The choice of an easterner with close links with the chief critics of monothelitism, Patriarch Sophronius of Jerusalem (634–8) and Maximus the Confessor (c. 580–662), can be explained by the need to elect a pope who could effectively resist the heretical view, imposed by the Byzantine court, that Christ had only one will. The short interval between his election and ordination indicates that the imperial mandate necessary for his consecration was obtained from the exarch at Ravenna, not from Constantinople.
One of Theodore's first acts was to write to the boy-emperor, Constans II (641–68), enquiring why the Ecthesis of Emperor Heraclius (610–41) was still in force, despite its repudiation by John IV and by Heraclius himself before his death. He wrote in similar terms to Paul II, the new patriarch of Constantinople (641–53), declining also to recognize him until his predecessor Pyrrhus I (638–41) had been canonically deposed by a synod at which the holy see must be represented, and demanding that Paul himself should repudiate the Ecthesis and have it removed from public places where it was posted. When Pyrrhus renounced monothelitism in 645 after being defeated in public debate by Maximus the Confessor and, having travelled to Rome, published a solemn recantation, Theodore received him with patriarchal honours and recognized him as rightful bishop of Constantinople. Pyrrhus' abjuration of monothelitism was received in the west as a notable triumph for orthodoxy, and the pope, encouraged by support from all quarters, did not hesitate to excommunicate and depose Patriarch Paul, who had now come out in favour of the Ecthesis. In the event Pyrrhus, disappointed in his hopes of actually recovering his throne, went to Ravenna, withdrew his recantation, and made peace with the court. In his fury Theodore excommunicated him too, signing the decree (it was said) on the Apostle's tomb in consecrated eucharistic wine.
In 648, convinced that the Ecthesis had failed to reconcile monophysites in the east and was so unpopular in the west as to threaten political stability, Constans II promulgated the edict known as the Typos, or ‘Rule’, which Paul had drafted. This abrogated the Ecthesis, prohibited all discussion on the number of wills and operations in Christ, and ordered that church teaching should be restricted to what had been defined by the five general councils. Subscription was obligatory, and when the papal apocrisiarius Anastasius refused to sign he was arrested and exiled to Trebizond; the Latin chapel in the Placidia Palace, official residence of the pope's nuncios, was shut down and its altar demolished. Theodore's attitude to the Typos would certainly have been hostile, but he died before being able to formulate it. Although chiefly known as the implacable foe of monothelitism, he was also generous to the poor of Rome and, among other modest building works, embellished S. Stefano Rotondo on the Caelian Hill on the occasion of the translation to it of the relics of SS. Primo and Feliciano (the first recorded translation of relics in the city).