When it is said
It stands near the start of nearly every service, and of morning and evening prayers at home. It heads a short set that prayer books call the Trisagion prayers. After it come “Glory to the Father”, a prayer to the All-holy Trinity, “Lord, have mercy” three times, and the Our Father.
It is sung at the Divine Liturgy, the Orthodox Communion service, just before the reading from the apostles’ letters. On a few great feasts another hymn takes its place. It also ends the Great Doxology, the morning hymn that begins “Glory to God in the highest”. At funerals it is sung as the body is carried out.
Where it comes from
No author known
First on record in AD 451
The first firmly dated record of the hymn comes from the Council of Chalcedon, a great gathering of bishops. At the close of its first session, on 8 October 451, the Eastern bishops and others cried it out.
The boy and the earthquake
St John of Damascus, a monk of the 700s, tells the story. Under Archbishop Proclus, in the 400s, Constantinople prayed to be spared a disaster. Angels taught the hymn to a boy lifted into the air. The people sang it, and the city was spared. The Orthodox Church remembers that disaster as an earthquake, on 25 September. Some historians think the hymn was already in use before that earthquake.
John of Damascus, An Exposition of the Orthodox Faith, Book 3, chapter 10; Orthodox Church in America, 25 September; Catholic Encyclopedia (1907), Agios O Theos
Sung to the whole Trinity
For the Orthodox the hymn speaks to the Trinity. St John of Damascus takes “Holy God” as the Father, “Holy Mighty” as the Son and “Holy Immortal” as the Holy Spirit. Yet each name still belongs to all three Persons.
John of Damascus, An Exposition of the Orthodox Faith, Book 3, chapter 10
What people get wrong
It is not “Holy, holy, holy”
The Trisagion is a different hymn from “Holy, holy, holy, Lord of hosts”, which is sung later in the Liturgy. That one is the song of the angels in Isaiah’s vision. The Trisagion takes up its threefold “Holy” in words of its own.
One word, three things
“Trisagion” is Greek for “thrice holy”. The word can mean the one-line hymn, the set of opening prayers built around it, or a short service of prayer for the departed, often held on the eve of a funeral. That service takes its name from the hymn that opens it.
Catholic Encyclopedia (1907), Agios O Theos; Orthodox Church in America, the Trisagion service
The Scripture in it
And they were calling out to one another: “Holy, holy, holy is the LORD of Hosts; all the earth is full of His glory.”
And each of the four living creatures had six wings and was covered with eyes all around and within. Day and night they never stop saying: “Holy, Holy, Holy, is the Lord God Almighty, Who was and is and is to come!”
Bible text: Berean Standard Bible, public domain.
In Greek
Ἅγιος ὁ Θεός, Ἅγιος Ἰσχυρός, Ἅγιος Ἀθάνατος,
ἐλέησον ἡμᾶς.
From the Great Doxology, the morning hymn that ends with this one, on Greek Wikisource.