(24 Dec. 640–12 Oct. 642)
A Dalmatian, son of a Venantius who was legal adviser (scholasticus) to the exarch at Ravenna, he was archdeacon of Rome when elected in Aug. 640. During the five-month interval while he awaited the imperial mandate then considered necessary for his consecration, the Roman church sent an authoritative letter to certain Irish bishops and abbots censuring their custom of observing Easter on the day of the Jewish Passover and warning them against Pelagianism. It is interesting that, while the pope-elect was the second signatory, the first was the archpriest Hilarus, and that Hilarus and the chief secretary (primicerius) John, also a signatory, described themselves as ‘vicegerents of the apostolic see’.
The exarch may have hoped that his official's son would accept the government's line on doctrinal matters, but in Jan. 641 John held a synod which condemned monothelitism, favoured by the Ecthesis of Emperor Heraclius (610–41), as heretical. In fact Heraclius, disappointed that the Ecthesis had resulted only in divisions, wrote to the pope shortly before his death (11 Feb. 641) disavowing monothelitism and making the previous patriarch Sergius I (610–38) responsible for the Ecthesis. When the new patriarch Pyrrhus I (638–41), in his propaganda to get the Ecthesis accepted in the west, appealed to Honorius I's endorsement of it, John wrote to Emperor Constantine III (Feb.–May 641) expressing disgust that attempts were being made to link Honorius with such heretical novelties; his predecessor, he argued tortuously, when he spoke of one will in Christ, had been thinking exclusively of his human will, which he held was free from the division to which human wills are normally subject as a result of the Fall (Rom. 7: 14–23). He also demanded that copies of the Ecthesis posted in public places in Constantinople should be pulled down.
Mindful of the plight of his homeland, John sent Abbot Martin to Dalmatia with substantial sums to ransom Christians enslaved by the Avar and Slav invaders. He also endowed a chapel next to the Lateran baptistery in honour of the saints of Dalmatia and filled it with relics of St Venantius (his own father's name) and other Dalmatian martyrs which Martin had brought to Rome. His portrait can still be seen there in the mosaic of the apse, which his successor Theodore I presented. On his death he granted his clergy a year's stipend each.
PL 80: 601–8Bede, Hist. eccl. 2. 19JW i. 227 f.LP i. 330Caspar ii. 365–8 (Davis 1: 68)DBI lv. 553–4 (L. Becto)DCB iii. 391 f. (J. Barmby)DTC viii. 597–9 (É. Amann)Bertolini 325 f.Levillain ii. 834 (J. Durliat)NCE vii. 921 (H. G. J. Beck)Seppelt ii. 57–9JR 182, 184