People: Holy, holy, holy, Lord Sabaoth, heaven and earth are filled with Your glory. Hosanna in the highest. Blessed is He who comes in the name of the Lord. Hosanna to God in the highest.
(The Holy Anaphora, The Divine Liturgy of St. John Chrysostom)
The Triumphal Hymn is a combination of the angelic hymn which Isaiah heard when he received his calling as a prophet, and the hymn with which the people received the Theanthropos in the Holy City of Jerusalem ‘as He was going to His voluntary Passion’. By singing this hymn at the Divine Liturgy, we are imitating both the angels and the people of the Holy City.
On the lips of the angelic powers, the Triumphal Hymn, as they sang it round the holy throne of God, had a double significance. It was a hymn of praise to the Trinitarian God, and at the same time a prophecy: “This hymn is not only a doxology, but also a prophecy of the good things that were going to spread throughout the world…The whole earth is full of His glory… (Isa. 6:3) When was the earth filled with the glory of God? When that hymn came down from heaven to earth, and mankind on earth formed one choir with the heavenly powers, raising the same melody to God and offering a common hymn of glory.” [St. John Chrysostom, Commentary on Isaiah, 6.3, P.G. 56.71] (Hieromonk Gregorios, The Divine Liturgy: A Commentary in the Light of the Fathers pp. 229-230)