When Sheroe rose in the kingdom, he desired and wished to live in his kingdom in peace...and by command and permission of his pacific majesty there was rest to all the churches that were under the dominion of the Persians. And [when] Mar Isho-yahbh from Beth-Arbhaye was appointed Patriarch, King Sheroe persuaded the Catholicus to select from the dominion of the East certain Metropolitans and bishops, that they might go up to the territory of the Byzantine Greeks...bearing his letters and greetings...Mar Isho-yahbh being obedient to the command of the good King Sheroe, gathered together Mar Cyriacus, the Metropolitan of Nisibis, and Mar Paul, Metropolitan of Adiabene, and Mar Gabriel of Karkha dhe Beth Selokh (Kerkuk) and certain other Bishops...and with them were also our holy Isho-yahbh of Nineveh and Sahadona. And thus through Christ our Lord, the Lord of the worlds and Governor and Guardian of the two countries and of the whole world gave these shepherds mercy in the sight of the Greeks, and they received their assembly and their petition as if they had been the angels of God. (Budge, E. A. Wallis. The book of governors: the Historia monastica of Thomas, bishop of Marga, A.D. 840, edited from Syriac manuscripts in the British museum and other libraries. London: K. Paul, Trench, Trübner & Co., 1893.(123-127))
The tale of the voyage gets more interesting when we turn to the same episode in history as recorded in the Chronique de Seert (my translation):
Isho-yahbh presented the proposal of Boran...also he presented him the gifts they had brought with them. Heraclius was surprised to learn that a woman had gained the crown. He was also amazed at the high bearing of the Catholicos, of his intelligence, and of his clear-sighted and scientific nature. The claimant [of the Roman Throne], interrogated [Isho-yahbh] about his faith, which he presented and described to him publicly, declaring that his profession of the faith is the same as that of the 318 [Fathers of Nicea]. [Isho-yahbh] also wrote for him the profession of faith of saint Mar Nestorius. The emperor favorably accepted the purpose of the embassy...he bestowed upon him all he desired, and commanded him [Isho-yahbh] to celebrate the liturgy en his presence that he may receive communion from [Isho-yahbh]. This he did.(Scher, Addai. Histoire nestorienne inédite: Chronique de Séert. Seconde partie. Patrologia Orientalis, 13.4 (1919) (557-558)).
Why, said [Heraclius], you go astray of the clearest manner in which to describe a thing, and instead of saying: Mary who bore God [Theotokos], you say: Mary who bore Christ who is God and man? We do not rule out the truth, replied the Catholicos, or the clear proof of it. By saying that Mary bore Christ, we imply that birth belongs to Christ, in which humanity is reunited to the eternal Word, who came down and lived in it. But if we say: Mary bore God, we reduce the name of humanity, by overtaking its nature. (Scher 559)
Then the emperor accepted the written profession of faith of Mar Isho-yahbh II and presented it to his "learned hierarchs" who approved the faith of the Church of the East and affirmed that there was no type of obstacle (Chronique 559). Now we turn to Mari ibn Sulaiman's De patriarchis nestorianorum for a final sense of where our two churches left off the last time we met. The emperor requested a libeleus of the faith of the Church of the East, which the patriarch provided. The emperor demanded that the bishops serve liturgies across the land, starting with a liturgy immediately celebrated there that Heraclius may commune from the hand of Isho-yahbh II. This happened, but first the patriarch needed to resolve the issue of the commemoration of Nestorius. The Emperor uttered these salient words (my translation):
If Nestorius had believed as you wrote the faith, he is by no means excommunicated, but if [he believed] another [faith] he is surely anathemized. It does not matter whether you commemorate him: we are yours and you are ours. (Maris, Amri et Slibae De patriarchis nestorianorum commentaria. Romae: De Luigi, 1896. (50))