Many monks contributed much toward a more just and moral society. From the ranks of the monks emerged the earliest condemnation of slavery. Gregory the Theologian, bishop of Nazianzus first, and later Patriarch of Constantinople, denounced the practice of holding slaves. His friend Basil of Ceasarea did not favor it but tolerated the institution as an established evil. Their contemporary Eustathios of Sebasteia condemned slavery and even advocated revolts by slaves. Later in the eighth and early ninth centuries, Theodore the Studite denounced slavery and forbade monks to possess, and the monastery to employ, slaves. In his rules for the hegoumenos of the Studios Monastery, Theodore advised: “You shall not possess a slave either for your own use or for your monastery or for the fields, since man was created in the image of God.” Eustathios, the twelfth century monk, archbishop of Thessaloniki, and critic and reformer of monasticism, condemned slavery as an evil and unnatural institution and advocated manumission.
– Christian Faith and Cultural Heritage: Essays from a Greek Orthodox Perspective, p. 162.
Symeon of Thessaloniki (+ 1429), in various questions set forth by the bishop of Pentapoleos Gregory, was asked the following question: “Which is more important and valuable, to help in the release of a captive or to distribute an amount to ten poor people?” Symeon’s position indicates the care of the Church which often emphasized the duty of Christians to liberate captives and slaves.
Generally the Byzantine community did not simply pray for “the captives and for their salvation” as one of the petitions of the Divine Liturgy says, but it offered what it could towards purchasing their release by often paying large sums.
– Poverty, Society, and Philanthropy in the Late Mediaeval Greek World
By Demetrios Constantelos