St. Demetrios the Great Martyr and Myrrhstreamer (Source)
Rejoice in the Lord, O city of Thessaloniki, exalt and dance, shining forth with faith, for Demetrios, the all-glorious Champion and Martyr of the truth holds you as a treasure in his bosom, and, beholding the receiving of wondrous healings, and seeing the casting down of the audacity of the Barbarians, give thanks to the Savior, crying out: Glory to You, O Lord.
-Idiomelon of the Litia in the First Tone, by George Sikeliotos
(source)
Through the prayers of our Holy Fathers, Lord Jesus Christ our God, have mercy on us and save us! Amen!