Saint Gerasimus was from the Peloponnesus, the son of Demetrius and Kale, of the family of Notaras. He was reared in piety by them and studied the Sacred writings. He left his country and went throughout various lands, and finally came to Cephalonia, where he restored a certain old church and built a convent around it, where it stands to this day at the place called Omala. He finished the course of his life there in asceticism in the year 1570. His sacred relics, which remain incorrupt, are kept there for the sanctification of the faithful.

When the fame of our Lord Jesus Christ came to Abgar, the ruler of Edessa, who was suffering from leprosy, Abgar sent a messenger named Ananias, through him asking the Savior to heal him of his disease, while bidding Ananias bring back a depiction of Him. When Ananias came to Jerusalem, and was unable to capture the likeness of our Lord, He, the Knower of hearts, asked for water, and having washed His immaculate and divine face, wiped it dry with a certain cloth, which He gave to Ananias to take to Abgar; the form of the Lord's face had been wondrously printed upon the cloth. As soon as Abgar received the cloth, which is called the Holy Napkin (Mandylion), he reverenced it with joy, and was healed of his leprosy; only his forehead remained afflicted. After the Lord's Death, Resurrection, and Ascension, the Apostle Thaddaeus (see Aug. 21) came to Edessa, and when he had baptized Abgar and all his men, Abgar's remaining leprosy also was healed. Abgar had the holy image of our Savior fixed to a board and placed at the city gate, commanding that all who entered the city reverence it as they passed through. Abgar's grandson, however, returned to the worship of the idols, and the Bishop of Edessa learned of his intention to replace the Holy Napkin with an idol. Since the place where it stood above the city gate was a rounded hollow, he set a burning lamp before the Holy Napkin, put a tile facing it, then bricked up the place and smoothed it over, so that the holy icon made without hands was no longer to be seen, and the ungodly ruler gave no further thought to it.

With the passage of time, the hidden icon was forgotten, until the year 615, when Chosroes II, King of Persia, was assaulting the cities of Asia, and besieged Edessa. The Bishop of Edessa, Eulabius, instructed by a divine revelation, opened the sealed chamber above the city gate and found the Holy Napkin complete and incorrupt, the lamp burning, and the tile bearing upon itself an identical copy of the image that was on the Holy Napkin. The Persians had built a huge fire outside the city wall; when the Bishop approached with the Holy Napkin, a violent wind fell upon the fire, turning it back upon the Persians, who fled in defeat. The Holy Napkin remained in Edessa, even after the Arabs conquered it, until the year 944, when it was brought with honor and triumph to Constantinople in the reign of Romanus I, when Theophylact was Ecumenical Patriarch. The Holy Napkin was enshrined in the Church of the most holy Theotokos called the Pharos. This is the translation that is celebrated today.

The holy Martyr Diomedes was from Tarsus in Cilicia, a physician who treated bodies with his healing art and souls with his piety. In the days of the Emperor Diocletian, about the year 288, Diomedes left Tarsus and came to Nicaea, where he benefited many both as a physician and as a preacher of the Faith. He was accused to Diocletian, who sent men to fetch him. When they arrived, although finding that he had already given up his soul to the Lord, they cut off his head to take it to the Emperor, and because of their inhumanity were stricken with blindness. When Diocletian saw the Saint's head, he commanded them to take it back and put it on the body in its place; when they had done so, they received their sight again. Saint Diomedes is one of the Holy Unmercenaries.