One unique thing about worship in an Orthodox Church is that almost the entire service is sung. But the singing is not simply songs of thanks and praise. The singing is not only the Gospels and Psalms but also “hymns and spiritual songs.” And these hymns and spiritual songs we sing are the theological teachings of the Church.
“All of our liturgical hymns are instructive, profound and sublime. They contain the whole of our theology and moral teaching, give us Christian consolation and instill in us a fear of the Judgment. He who listens to them attentively has no need of other books on the Faith. St. Theophan the Recluse.
According to the New Testament, Our Lord took three of His disciples Sts. Peter, James, and John, to the top of Mt. Tabor, where He was transfigured by showing them some of His glory as much as they could handle, in the presence of the two Holy Prophets Elijah and Moses. The hymns of the Feast of the Transfiguration find it very significant that The Lord’s Transfiguration took place before his arrest. The songs for the day reflect on the disciples witnessing His awesome glory and tremendous power, and then they see Him humiliated in the most disgraceful ways, and eventually put on The Cross. Then they could realize that He suffered everything because of His infinite, truthful, and unconditional love towards each one of us individually, and that He wants all of us to be with Him eternally.
You were transfigured on the Mount, Christ God revealing Your glory to Your disciples, insofar as they could comprehend. Illuminate us sinners also with Your everlasting light, through the intercessions of the Theotokos. Giver of light, glory to You.
You were transfigured upon the Mount, O Christ our God, and Your disciples, in so far as they could bear, beheld Your glory. Thus, when they see You crucified, they may understand Your voluntary passion, and proclaim to the world that You are truly the effulgence of the Father.