Two sixth century historians, Procopius and Evagrius, speak of a miracle with a large fragment of the True Cross that took place in their time in the city of Apamea in 540 A.D., just after the Persians under Chosroes seized Antioch. The two authors narrate below from eye-witness testimony.
(History of the Wars, Bk. 2, Ch. 11)
But Chosroes [531-579] with his whole army proceeded on the way to Apamea. Now there is a piece of wood one cubit in length in Apamea, a portion of the cross on which Christ in Jerusalem once endured the punishment not unwillingly, as is generally agreed, and which in ancient times had been conveyed there secretly by a man of Syria. And the men of olden times, believing that it would be a great protection both for themselves and for the city, made for it a sort of wooden chest and deposited it there; and they adorned this chest with much gold and with precious stones and they entrusted it to three priests who were to guard it in all security; and they bring it forth every year and the whole population worship it during one day. Now at that time the people of Apamea, upon learning that the army of the Medes was coming against them, began to be in great fear. And when they heard that Chosroes was absolutely untruthful, they came to Thomas, the bishop of the city, and begged him to shew them the wood of the cross, in order that after worshiping it for the last time they might die. And he did as they requested. Then indeed it befell that a sight surpassing both description and belief was there seen. For while the priest was carrying the wood and shewing it, above him followed a flame of fire, and the portion of the roof over him was illuminated with a great and unaccustomed light. And while the priest was moving through every part of the temple, the flame continued to advance with him, keeping constantly the place above him in the roof. So the people of Apamea, under the spell of joy at the miracle, were wondering and rejoicing and weeping, and already all felt confidence concerning their safety. And Thomas, after going about the whole temple, laid the wood of the cross in the chest and covered it, and suddenly the light had ceased. Then upon learning that the army of the enemy had come close to the city, he went in great haste to Chosroes. And when the king inquired of the priest whether it was the will of the citizens of Apamea to marshal themselves on the wall against the army of the Medes, the priest replied that no such thing had entered the minds of the men. "Therefore," said Chosroes, "receive me into the city accompanied by a few men with all the gates opened wide." And the priest said "Yes, for I have come here to invite thee to do this very thing." So the whole army pitched their tents and made camp before the fortifications.
Then Chosroes chose out two hundred of the best of the Persians and entered the city. But when he had got inside the gates, he forgot willingly enough what had been agreed upon between himself and the ambassadors, and he commanded the bishop to give not only one thousand pounds of silver nor even ten times that amount, but whatsoever treasures were stored there, being all of gold and silver and of marvellous great size. And I believe that he would not have shrunk from enslaving and plundering the whole city, unless some divine providence had manifestly prevented him; to such a degree did avarice overpower him and the desire of fame turn his mind. For he thought the enslavement of the cities a great glory for himself, considering it absolutely nothing that disregarding treaties and compacts he was performing such deeds against the Romans. This attitude of Chosroes will be revealed by what he undertook to do concerning the city of Daras during his withdrawal at this same time, when he treated his agreements with absolute disregard, and also by what he did to the citizens of Callinicus a little later in time of peace, as will be told by me in the following narrative. But God, as has been said, preserved Apamea. Now when Chosroes had seized all the treasures, and Thomas saw that he was already intoxicated with the abundance of the wealth, then bringing out the wood of the cross with the chest, he opened the chest and displaying the wood said: "O most mighty King, these alone are left me out of all the treasures. Now as for this chest (since it is adorned with gold and precious stones), we do not begrudge thy taking it and keeping it with all the rest, but this wood here, it is our salvation and precious to us, this, I beg and entreat thee, give to me." So spoke the priest. And Chosroes yielded and fulfilled the request.
By Evagrius Scholasticus
(Ecclesiastical History, Bk. 4, Ch. 26)
Now that I have arrived at this point of my narrative, I will relate a prodigy, which occurred at Apamea, and is worthy of a place in the present history.
When the sons of the Apameans were informed that Antioch had been burnt, they besought the before-mentioned Thomas [bishop of Apamea] to bring forth and display the saving and life-giving wood of the cross, in deviation from established rule, that they might behold and kiss for the last time the sole salvation of man, and obtain a provision for the passage to another life, in having the precious cross as their means of transport to the better lot. In performance of which request, Thomas brings forth the life-giving wood, announcing stated days for its display, that all the neighboring people might have an opportunity to assemble and enjoy the salvation thence proceeding.
Accordingly, my parents visited it together with the rest, accompanied by myself, at that time a school-boy. When, therefore, we requested permission to adore and kiss the precious cross, Thomas, lifting up both his hands, displayed the wood which blotted out the ancient curse, making an entire circuit of the sanctuary, as was customary on the ordinary days of adoration. As Thomas moved from place to place, there followed him a large body of fire, blazing but not consuming; so that the whole spot where he stood to display the precious cross seemed to be in flames, and this took place not once or twice but often, as the priest was making the circuit of the place, and the assembled people were entreating him that it might be done. This circumstance foreshewed the preservation which was granted to the Apameans. Accordingly, a representation of it was suspended on the roof of the sanctuary, explaining it by its delineation to those who were uninformed, which was preserved until the irruption of Adaarmanes and the Persians, when it was burnt together with the holy church in the conflagration of the entire city. Such were these events. But Chosroes, in his retreat, acted in direct violation of conditions--for even on this occasion terms had been made--in a manner suited to his restless and inconstant disposition, but utterly unbecoming a rational man, much more a king professing a regard for treaties.