ISÒ' BAR NÙN. - Nestorian Katholikós, elected in 823 at the age of 80 and died in 828.
He wrote: *Questions on Holy Scripture*, a juridical work *Canons and Laws*, homilies, and *Responses to Questions of the Deacon Macarius*, of liturgical content.
BIBL.: A. Baumstark, *Geschichte der syrischen Literatur*, Bonn 1922, pp. 219-220; J. B. Chabot, *Littérature syriaque*, Paris 1934, pp. 109-110.
Guglielmo de Vries