In his second homily on the Dormition of the Theotokos, Saint John of Damascus refers to events recounted in the 40th chapter of the Life of St Euthymios:
It was said above that Saint Pulcheria erected many churches for Christ in Constantinople. One of these is the church in Blachernae, built at the beginning of the reign of the divinely-appointed Emperor Marcian [who acceded to the throne August, 450]. When the two of them built a worthy house there for the all-glorious and all-holy Mother of God, the ever-virgin Mary, and adorned it with every sort of decoration, they hoped to find her holy body, which had been the dwelling-place of God. And summoning Juvenal, the Archbishop of Jerusalem, and those bishops from Palestine who were staying in the capital because of the synod then being held in Chalcedon [October, 451], they said to them: We have heard that the first and most outstanding church of the all-holy Mother of God, the ever-virgin Mary, is in Jerusalem, in the place called Gethsemane, where her life-giving body was put in a coffin. We now wish to bring this relic here, to protect this royal city.”
Juvenal answered on behalf of them all: “There is nothing in the holy, inspired Scripture about the death of Mary, the holy Mother of God; but we know from ancient and wholly reliable tradition that at the time she so gloriously fell asleep, all the holy Apostles who were traveling the world for the salvation of the peoples were lifted up in a single instant of time and were gathered at Jerusalem. And as they stood by her, they saw a vision of angels, and heard the divine chanting of the higher powers. So it was that she gave her soul in an ineffable way into God’s hands, surrounded by the glory of God and all heaven.
“Her body, which had been God’s dwelling place, was brought for burial amidst the singing of the angels and the Apostles, and laid to rest in a coffin in Gethsemane; and the angelic dancing and singing continued without pause in that place for three days. But after three days the song of the angels ceased; the Apostles were there, and since one of them – Thomas – had not been present [for her burial] and came at he end of three days, and wished to reverence that body which had housed God, they opened the coffin. And they could not find her body, which had been the object of such praise; all that they found were her burial wrappings. And being overcome by the ineffable fragrance that came out of the wrappings, they closed the coffin again. Amazed by this miraculous discovery, they could only draw a single conclusion: The one who had deigned to become flesh in her own person and to take his humanity from her, the one who willed to be born in human flesh as God the Word, the Lord of glory, and who had preserved her virginity intact even after childbirth, now chose, after her departure from this world, to honor her pure and immaculate body with the gift of incorruptibility, and with a change of state even before the common, universal resurrection.”
When the imperial couple heard this, they asked Archbishop Juvenal to send them the holy coffin, properly sealed, with the funeral garments in it of the glorious, all-holy Mary, Mother of God.
And when he had sent it, they placed it in the church of the holy Theotokos that had been built at Blachernae.