This glorious and wonderworking saint was born in Thessalonica of noble and devout parents. Implored of God by childless parents, Demetrios was their only son, and so was raised and educated with great care. Demetrios’s father was a commander in Thessalonica. When his father died, Emperor Maximian appointed Demetrios as commander in his place. As he appointed him, Maximian, an opponent of Christ, particularly recommended that he persecute and exterminate the Christians in Thessalonica. Demetrios not only disobeyed the emperor but openly confessed and preached the Lord Jesus Christ in the city of Thessalonica. When the emperor heard of this he became furious with Demetrios. Then, when he was returning from battle against the Sarmatians, Maximian stopped at Thessalonica to investigate the matter. The emperor summoned Demetrios and questioned him about his faith. Demetrios openly acknowledged his Christian Faith to the emperor and also denounced the emperor’s idolatry. Maximian cast Demetrios into prison. Knowing what was awaiting him, Demetrios gave all his goods to his faithful servant Lupus to distribute to the poor, and joyfully awaited his imminent suffering for Christ the Lord. An angel of God appeared to him in prison, saying: “Peace be to you, O sufferer of Christ; be brave and be strong!” After several days, the emperor sent soldiers to the prison to kill Demetrios. The soldiers found the saint of God at prayer and ran him through with lances. Christians secretly took his body and honorably buried it. Healing myrrh flowed from the body of the martyr of Christ, curing many of the sick. Soon, a small church was built over his relics.
An Illyrian nobleman, Leontius, was afflicted with an incurable illness. He hastened, with prayer, to the relics of St. Demetrios and was completely healed. In thanksgiving, Leontius erected a much larger church on the site of the old church. The saint appeared to him on two occasions. When Emperor Justinian wanted to translate the relics of the saint from Thessalonica to Constantinople, flaming sparks sprang from the tomb and a voice was heard: “Stop, and do not touch!” And thus, the relics of St. Demetrios have remained for all time in Thessalonica. As the protector of Thessalonica, St. Demetrios has appeared many times, and on many occasions has saved Thessalonica from great calamity. His miracles are without number. The Russians considered St. Demetrios to be the protector of Siberia, which was conquered and annexed to Russia on October 26, 1581.
Source: St. Nikolai Velimirovic, The Prologue of Ohrid – Volume Two.
The world has found in you a great champion in time of peril, as you emerged the victor in routing the barbarians. For as you brought to naught the boasts of Lyaios, imparting courage to Nestor in the stadium, in like manner, holy one, great Martyr Demetrios, invoke Christ God for us, that He may grant us His great mercy.
God, who gave you invincible power and with care kept your city invulnerable, royally clothed the Church in purple with the streams of your blood, for you are her strength, O Demetrios.