He was later captured by the Dailamites who were at war with the invading Arabs and was carried away to the Daylam region in southern shores of the Caspian Sea.
As a reward the monk asked for a Kharaj-free land in Fars, in south-western Persia, to build a monastery there.
[2] The Syriac Life mentions a visit by John to Bakhdida where he converted its inhabitants to Christianity and founded a monastery which still bears his name.
This is however a later addition to the hagiography by a West Syrian author who wished to conceal the "Nestorian" past of the town.
He also founded another monastery near Kashkar which was assigned to the Syriac-speaking community in order to resolve a conflict between the Syriac- and Persian-speaking monks of the region.