The feast celebrated in the West as "Epiphany" (highlighting the Magi) is observed in the East as the "Theophany," centered on the baptism and especially the manifestation of the Trinity: the voice of the Father, the Beloved Son, the Spirit in the form of a dove. Later, in the West, we added an additional feast of the Baptism of the Lord on the Sunday following Epiphany.
Here is, in any case, the culmination of our celebration of God's showing Himself to the world. Henceforth Jesus will bear witness to His Father in the Spirit, from Galilee to Judea to the Cross. God has entered our history in all the depths of His love. He reveals His Glory; He reveals that He is Love.
When You, O Lord were baptized in the Jordan
The worship of the Trinity was made manifest For the voice of the Father bore witness to You
And called You His beloved Son.
And the Spirit, in the form of a dove,
Confirmed the truthfulness of His word.
O Christ, our God, You have revealed Yourself
And have enlightened the world, glory to You!
Troparion, Theophany,
Byzantine Liturgy