:"...That on this emergency he had exhorted the faithful to devote a whole week to uninterrupted [[fasting]] and public supplication in the churches, rests only on the authority of one passage, in the ''Religiosa Historia'' of [[Theodoret of Cyrrhus|Theodoret]], the spuriousness of which is acknowledged by all sound critics. The gross blunders of making the death of the heresiarch contemporaneous with the Council of Nicaea, and of confounding [[Alexander of Alexandria]] with [[Alexander of Constantinople]], prove it to be an ignorant forgery. In the account of the death of [[Arius]] given by Theodoret, in his ''Ecclesiastical History'', from Athanasius (Theod. ''H. E.'' i. 14; Soz. ''H. E.'' ii. 20.) no mention is made of Jacob in connection with the death of Arius; and he is equally absent from that given by [[Athanasius of Alexandria|Athanasius]] in his letter to the bishops." (Sir William Smith. ''"[http://books.google.ca/books?id=7eItAAAAIAAJ&printsec=frontcover#v=onepage&q&f=false JACOBUS (4) or JAMES bishop of Nisibis in Mesopotamia]".'' In: '''Volume 3 of A Dictionary of Christian Biography, Literature, Sects and Doctrines: Being a Continuation of 'The Dictionary of the Bible'.''' J. Murray, 1882. p.326.)</ref>
Writer'''<br>No writings of Jacob of Nisibis are known, although he has been confused in the past with the fourth century Persian writer [[w:Aphrahat|Aphrahat]] (ca.270-ca.345), head of the monastery of [[w:Mar Mattai Monastery|Mar Mattai]], near modern Mosul, with the rank of [[bishop]] and, apparently, the episcopal name Jacob, who composed a series of twenty-three expositions or homilies on points of Christian doctrine and practice.<ref group="note">According to Professor T.D. Barnes (University of Toronto):<br>:The twenty-three Demonstrations of [[w:Aphrahat|Aphrahat]] are not likely to be familiar to most students of Roman history or of Constantine. Aphrahat was head of the monastery of [[w:Mar Mattai Monastery|Mar Mattai]], near modern Mosul, with the rank of [[bishop]] and, apparently, the episcopal name Jacob: as a consequence, he was soon confused with the better known Jacob of Nisibis, and independent knowledge of his life and career virtually disappeared. Fortunately, however, twenty-three treatises survived, whose attribution to 'Aphrahat the Persian sage' seems beyond doubt. Aphrahat wrote in Syriac and composed works of edification and polemic for a Mesopotamian audience outside the Roman Empire. (T. D. Barnes. ''"Constantine and the Christians of Persia."'' '''The Journal of Roman Studies.''' Vol. 75 (1985), pp. 126-136. Page 126.)</ref>
The author of the homilies, who was earliest known as "the Persian sage", was a Persian subject, and tells us that he took the Christian name ''Jacob'' at his baptism. Hence he was already confused with Jacob of Nisibis by the time of [[ w:Gennadius of Massilia| Gennadius]] (before 496), <ref group="note">[[w:Gennadius of Massilia|Gennadius]] speaks of Jacob as a copious writer, and gives the titles of twenty-six different treatises of which he was the author. <br> :"These, or some of them, eighteen in number, were found by [[ w:Giuseppe Simone Assemani|Assemani]] in the [[w:Mechitarists|Armenian convent of St. Anthony at Venice]]...The titles of these treatises - '' De Fide, De Dilectione, De Jejunio, De Oratione, De Bello, De Devotis, De Poenitentia, De Resurrectione,'' etc. - correspond generally with those given by [[w:Gennadius of Massilia|Gennadius]], but the order is different. In the same collection he found the letter of Jacob to the bishops of Seleucia and Ctesiphon, on the Assyrian schism. It is a lengthy document, in thirty-one sections, lamenting the divisions of the church and the pride and arrogance which were their cause, and exhorting them to study peace and concord. These were all published with a Latin translation and a learned preface establishing their authenticity and notes by [[w: Nicolò Maria Antonelli| Nicholas Maria Antonelli]] in 1756. They were also printed in the collection of the [[w:Mechitarists|Armenian fathers]], published at Venice in 1765, and again at Constantinople in 1824. The Latin translation is found in the '' Patres Apostolici'' of [[w:Armand-Benjamin Caillau|Caillau]], tom. 25, pp.254-543." (Sir William Smith. '' "[http://books.google.ca/books?id=7eItAAAAIAAJ&printsec=frontcover#v=onepage&q&f=false JACOBUS (4) or JAMES bishop of Nisibis in Mesopotamia]".'' In: '''Volume 3 of A Dictionary of Christian Biography , Literature, Sects and Doctrines: Being a Continuation of ' The Dictionary of the Bible'. ''' J. Murray, 1882. p. 326. )</ref> and the ancient Armenian version of nineteen of the homilies was published under this latter name.
The [[Venerable]] Bishop Jacob died peacefully in Nisibis, according to some in A.D. 338,<ref name="SOCA"/><ref name="ASOC"/><ref name="CCEL"/> and according to others in A.D. 350.<ref name="SMITH"/><ref name="S.V.BULGAKOV"/><ref name="BARTLEBY"/>
He was honourably interred within the city, in pursuance, it is said, of an express charge of [[Constantine the Great]] to his son Constantius, indicative of the reverance he held for him, that after death his [[Relics|hallowed remains]] might continue to defend Nisibis against its enemies.