He wrote to the clergy of Ireland and Scotland to tell them of the mistakes they were making with regard to the time of keeping Easter and condemned Monothelitism as heresy.

[3] While still only pope-elect, John, with the other bishops of the Catholic Church, wrote to the clergy of Ireland and Scotland to tell them of the mistakes they were making with regard to the time of keeping Easter, and exhort them to be on their guard against the Pelagian heresy.

[3] Troubles in his native land caused by the invasions of Slavs directed John's attention there.

To alleviate the distress of the inhabitants, John sent the abbot Martin into Dalmatia and Istria with large sums of money for the redemption of captives.

As the ruined churches could not be rebuilt, the relics of some of the more important Dalmatian saints were brought to Rome.