The Holy Martyr Eustathius was a soldier. He was arrested and brought before the head of the city of Ancyra for confessing the Christian Faith. At the interrogation, the saint firmly and bravely confessed himself a Christian and was sentenced to tortures. They beat him without mercy, they bore into the heels and, having tied him with rope, they dragged him in the city to the River Sagka (Sangara).

At the bank of the river they put the martyr into a wooden chest and threw it in the water, but an angel of God brought the chest to shore. The saint, in the chest, was singing the 90th (91st) Psalm: "He who dwelleth in the help of the Most High..." Beholding the miracle and sensing himself disgraced, the governor drew his sword and killed himself. The holy martyr, having received Communion from the hand of an angel, gave up his soul to God. His holy relics were buried in the city of Ancyra.