Can deacons celebrate the Divine Liturgy?
No. Deacons in the Eastern Churches do not celebrate the Sacraments, but assist at the Liturgical services. During the Divine Liturgy, they proclaim the Gospel of the Lord. In recent years, where no priest was available, deacons have been authorized to celebrate a kind of presanctified liturgy. Due to lack of available texts, the faithful used the ordinary text of the Divine Liturgy, with the deacon omitting the Eucharistic Prayers of consecration.
