Saint John, a pious Christian soldier, lived in Edessa during the persecution by Diocletian (284-305). When the persecution started, he went to Jerusalem and there he heard about Saint Cyrus. He began to search for him, going first to Alexandria and then to Arabia. When Saint John finally found Saint Cyrus, he remained with him and became his faithful follower.

They learned of the arrest of the Christian woman Athanasia and her three young daughters. Theoctiste was fifteen; Theodota, was thirteen; and Eudoxia, was eleven. Saints Cyrus and John hastened to the prison to help them. They were concerned that faced with torture, the women might renounce Christ.

Saints Cyrus and John gave them courage to endure what lay before them. Learning of this, the ruler of the city arrested Saints Cyrus and John, and seeing their steadfast and fearless confession of faith in Christ, he brought Athanasia and her daughters to witness their torture. The tyrant did not refrain from any form of torture against the holy martyrs. The women were not frightened by the sufferings of Saints Cyrus and John, but courageously continued to confess Christ. They were flogged and then beheaded, receiving their crowns of martyrdom.

At the same place they executed the Holy Unmercenaries Cyrus and John. Christians buried their bodies in the church of the holy Evangelist Mark. In the fifth century the relics of Saints Cyrus and John were transferred from Canopis to Manuphin. Later on their relics were transferred to Rome, and from there to Munchen (Munich) (another account is located under June 28).

Saints Cyrus and John are invoked by those who have difficulty in sleeping.

Source:

https://oca.org/saints/lives/2017/01/31/100381-wonderworker-and-unmercenary-john