The Trisagion (literally, “thrice holy”) hymn is found in all Eastern Liturgies, and is said to come to us from the angels. According to legend, a severe earthquake shook the capitol of the Empire while Saint Proclus, patriarch of Constantinople (434-446), was leading the people in prayer. It is said that a young boy was lifted into the air and heard the angels singing, “Holy God, Holy Mighty One, Holy Immortal One, have mercy on us.” The boy told the people to sing this hymn, and when they did, the earthquake ceased.
While scholars today dismiss the account (for
one thing, there is no record of an earthquake in Constantinople during the
patriarchate of Proclus), nevertheless it cannot be disputed that the
Trisagion comes from the angels. The hymn is in part inspired by the vision
granted to Isaiah of the angels gathered around the throne of God
singing, “Holy, holy, holy is the Lord Almighty; the whole earth is full of
His glory.”122
The apostle John was granted the same angelic vision while on the isle of Patmos: “Holy, holy, holy, Lord God Almighty, who was and is and is to come.”123 The title “Mighty One” is probably from Psalm 45:3, while “Immortal One” may have been inspired by Psalms 102:26-27 and 90:2-4.124 The Trisagion was first introduced into the Liturgy in Constantinople between 430 and 450, and was subsequently sung by the Fathers of the Fourth Ecumenical Council at Chalcedon (451).
The Trisagion is always solemnly chanted before the reading of the Epistle. One of the reasons the Church included the Trisagion into the Liturgy was to show that angels and mortals form one Church, a single choir. Because of the coming of Christ, there is now a bridge between heaven and earth and we can now join the angles in giving perfect glory to God. In the Orthodox tradition, the hymn is essentially Trinitarian:125
“Holy God,” referring to the Father.
“Holy Mighty One,” i.e. the Son, Who bound the devil and made him powerless
through the Cross, trampling down death by death.
“Holy Immortal One,” the Holy Spirit, the Giver of Life, through Whom all
Creation receives life.
Because the Trisagion is considered to be a reference to the all-holy Trinity, the Faithful usually make the sign of the cross while it is sung.
After the Trisagion, the priest, turning towards the bishop’s throne behind the Holy Table, then says: “Blessed is he who comes in the name of the Lord.”126 This is what was said as the Lord made His entrance into Jerusalem on a colt during Holy Week, fulfilling the prophecy from Zechariah 9:9 that “your king,” the Messianic King of Israel, would come riding on a donkey. It was this Messianic expectation which led crowds to gather around the road leading into the city to greet Jesus, shouting, “Blessed is he who comes in the name of the Lord!” This is from Psalm 118:26, a psalm especially loaded with prophetic allusions to the Messiah.
The Talmud contains a fascinating homily on the prophecy that the Messiah would come on a colt: “Rabbi Alexandri said, `Rabbi Y’hoshua set two verses against each other: It is written, “And behold, one like the son of man came with the clouds of heaven” (Daniel 7:13), while elsewhere it is written, “See, your king comes to you,...humbly riding on a donkey” (Zechariah 9:9). [He resolved the paradox by saying that] if they deserve it [he will come] with the clouds of heaven, but if not, lowly and riding on an ass.'”127 The rabbis were combining Christ’s two entrances into the world: His first in humility, riding on an ass, and His second in power and glory. The New Testament, on the other hand, distinguishes Christ’s two comings into the world.
Thus in the Little Entrance, Christ’s first entrance into the world is signified by the Gospel reading which tells us of His Incarnation two thousand years ago. This is also signified by the singing of, “Blessed is he who comes in the name of the Lord,” which recalls Jesus’ entrance into Jerusalem during Holy Week.
The second and glorious entrance into the world as King of kings and Lord of lords is signified by Christ’s enthronement on the Holy Table, after which the priest says: “Blessed are You, seated above the Cherubim on the throne of the glory of Your kingdom: always, now and ever, and to the ages of ages.”
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122 Isaiah 6:3.123 Revelation 4:8.
124 Also, the apostle Paul wrote that the Lord is “King eternal, immortal (aphtharton)” (1 Timothy 1:17), and He “alone is immortal
(athanasian)” (1 Timothy 6:16).
125 The Jacobite Patriarch Peter the Fuller (468/70-488) early on in his episcopate added the phrase, “who was crucified for us”, after, “Immortal One.” This made the Trisagion a strictly Christological hymn in the Non-Chalcedonian churches. The purpose of the addition was to stress that it is perfectly proper to say that God died for us. 126 Matthew 21:9.
127 Sanhedrin 98a. Cited by David Stern in The Jewish New Testament Commentary (Clarksville, MD:Jewish New Testament
Publications, 1992), 62.