The 14th-century Archbishop of Thessalonica who defended hesychast spirituality and taught about the uncreated energies of God. Celebrated on the Second Sunday of Lent, Palamas developed theological foundations for mystical prayer and the Jesus Prayer tradition. His teachings on theosis (deification) are central to Orthodox spiritual life.

The central worship service of the Orthodox Church, celebrating the Eucharist (Holy Communion). Usually celebrated on Sundays and feast days, the Divine Liturgy consists of the Liturgy of the Word (scripture readings) and Liturgy of the Faithful (Eucharistic prayer and communion). The most common forms are the Liturgies of St. John Chrysostom and St. Basil the Great.

A special Lenten service combining Vespers with communion using bread consecrated at a previous Divine Liturgy. Celebrated on Wednesday and Friday evenings during Great Lent, this service allows the faithful to receive communion during the fasting period without celebrating the full Divine Liturgy. It maintains the penitential character of Lent while providing spiritual nourishment.

A lengthy service combining Vespers and Matins, traditionally celebrated on the eve of Sundays and major feasts. The All-Night Vigil includes the singing of "Lord, I Call," the Magnificat, the Great Doxology, and numerous psalms and hymns. This service prepares the faithful spiritually for the upcoming feast.

The evening prayer service of the Orthodox Church, traditionally celebrated at sunset. Vespers includes psalms, hymns, scripture readings, and incense. On Saturday evenings, Great Vespers is often combined with the Sunday Divine Liturgy. The service marks the end of the liturgical day and prepares the faithful for rest and reflection.

The Archangel Gabriel's announcement to the Virgin Mary that she would bear the Son of God. Celebrated on March 25th, exactly nine months before Christmas, this feast honors Mary's "Yes" to God's plan of salvation. The service emphasizes both the Incarnation of Christ and the Theotokos's role in our redemption.