Trisagion

Trisagion (”thrice holy”)

Ἅγιος ὁ Θεός
Ἅγιος ἰσχυρός
Ἅγιος ἀθάνατος
ἐλέησον ἡμᾶς 

“Holy God,
Holy [and] mighty
Holy [and] immortal
Have mercy on us”

The trisagion is an ancient hymn that is part of the Eastern Orthodox liturgy, called the “Divine Liturgy”. It is sung during the Liturgy of the Catechumens, so called because in the early church, the service was divided between that which the catechumens (those people who were learning the faith in ‘classes’ before baptism) could attend, and that which was for members of the church only. The transliteration is as follows:

“Hagios ho theos
hagios ischuros
hagios athanatos
eleêsan hêmas”