Intrigues not very dissimilar in their character had been previously employed to remove Bahram, whom the Persian monarch had not ceased to fear, notwithstanding that he was a fugitive and an exile. The Khan of the Turks had received him with honor on the occasion of his flight, and, according to some authors, had given him his daughter in marriage. Chosroes lived in dread of the day when the great general might reappear in Persia, at the head of the Turkish hordes, and challenge him to renew the lately-terminated contest.
He therefore sent an envoy into Turkestan, well supplied with rich gifts, whose instructions were to procure by some means or other the death of Bahram. Having sounded the Khan upon the business and met with a rebuff, the envoy addressed himself to the Khatun, the Khan's wife, and by liberal presents induced her to come into his views. A slave was easily found who undertook to carry out his mistress's wishes, and Bahram was despatched the same day by means of a poisoned dagger. It is painful to find that one thus ungrateful to his friends and relentless to his enemies made, to a certain extent, profession of Christianity. Little as his heart can have been penetrated by its spirit, Chosroes seems certainly, in the earlier part of his reign, to have given occasion for the suspicion, which his subjects are said to have entertained, that he designed to change his religion, and confess himself a convert to the creed of the Greeks. During the period of his exile, he was, it would seem, impressed by what he saw and heard, of the Christian worship and faith; he learnt to feel or profess a high veneration for the Virgin; and he adopted the practice, common at the time, of addressing his prayers and vows to the saints and martyrs, who were practically the principal objects of the Oriental Christians' devotions. Sergius, a martyr, hold in high repute by the Christians of Osrhoene and Mesopotamia, was adopted by the superstitious prince as a sort of patron saint; and it became his habit, in circumstances of difficulty, to vow some gift or other to the shrine of St. Sergius at Sergiopolis, in case of the event corresponding to his wishes. Two occasions are recorded where, on sending his gift, he accompanied it with a letter explaining the circumstances of his vow and its fulfilment; and even the letters themselves have come down to us, but in a Greek version. In one, Chosroes ascribes the success of his arms on a particular occasion to the influence of his self-chosen patron; in the other, he credits him with having procured by his prayers the pregnancy of Sira (Shirin), the most beautiful and best beloved of his wives. It appears that Sira was a Christian, and that in marrying her Chosroes had contravened the laws of his country, which forbade the king to have a Christian wife. Her influence over him was considerable, and she is said to have been allowed to build numerous churches and monasteries in and about Ctesiphon. When she died, Chosroes called in the aid of sculpture to perpetuate her image, and sent her statue to the Roman Emperor, to the Turkish Khan, and to various other potentates.