Constantine’s parents were Emperor Constantius Chlorus and Empress Helen. Chlorus had other children by another wife, but from Helen he had only Constantine. After his coronation Constantine fought three great battles: the first against Maxentius, a Roman tyrant; the second against the Scythians on the Danube; and the third against the Byzantines. Before the battle with Maxentius, while Constantine was greatly concerned and doubtful of his success, a brilliant Cross appeared to him in the sky during the day, adorned with stars. Written on the Cross were the words: “By this Sign Conquer.” Astonished, the emperor ordered a large cross to be forged, like the one that had appeared, and that it be carried before the army into battle. By the power of the Cross he achieved a glorious victory over the enemy, which was greatly superior in number. Maxentius drowned in the Tiber River. Immediately after this, in the year 313, Constantine issued the famous Edict of Milan to halt the persecution of Christians. Defeating the Byzantines, Constantine built a beautiful capital on the Bosphorus, which from that time was called Constantinople. Before this, however, Constantine fell ill with the dreaded disease of leprosy. As a cure, the pagan priests and physicians counseled him to bathe in the blood of slaughtered children. However, he rejected that. Then the Apostles Peter and Paul appeared to him and told him to seek out Bishop Sylvester, who would cure him of this dreaded disease. The bishop instructed him in the Christian Faith and baptized him, and the disease of leprosy vanished from the emperor’s body. When a discord began in the Church because of the mutinous heretic Arius, the emperor convened the First Ecumenical in Nicaea in 325, at which the Arian heresy was condemned and Orthodoxy confirmed. St. Helen, the pious mother of the emperor, was very zealous for the Faith of Christ. She visited Jerusalem, discovered the Honorable Cross of the Lord, and built the Church of the Resurrection on Golgotha, as well as many other churches throughout the Holy Land. This holy woman presented herself to the Lord in her eightieth year, in 327. Emperor Constantine outlived his mother by ten years. He reposed in Nicomedia in his sixty-fifth year, in 337. His body was interred in the Church of the Twelve Apostles in Constantinople.
Source: St. Nikolai Velimirovic, The Prologue of Ohrid – Volume One.
Today, Constantine with his mother Helen present the Cross, the most precious wood. It shames unbelievers. It is a weapon of faithful kings against their adversaries. A great sign has come forth for us which is awesome in battle.