He is not present typically, nor figuratively, nor by superabundant grace, as in the other Mysteries, nor by a bare presence, as some of the Fathers have said concerning Baptism, or by impanation, so that the Divinity of the Word is united to the set forth bread of the Eucharist hypostatically, as the followers of Luther most ignorantly and wretchedly suppose.
But truly and really, so that after the consecration of the bread and of the wine, the bread is transmuted, transubstantiated, converted and transformed into the true Body itself of the Lord, Which was born in Bethlehem of the ever-Virgin, was baptized in the Jordan, suffered, was buried, rose again, was received up, sits at the right hand of the God and Father, and is to come again in the clouds of Heaven; and the wine is converted and transubstantiated into the true Blood itself of the Lord, Which as He hung upon the Cross, was poured out for the life of the world.
Orthodox Confession of Dositheus, Patriarch of Jerusalem (1672)