TRISAGION - (1) Literally, "Thrice Holy." The biblical Trisagion, "Holy, Holy, Holy," is the hymn of the angels before the throne of God (Is. 6:1-3; Rev. 4:8), and is one of the most important hymns of the Divine Liturgy. In the Tradition of the Church, this hymn has been amplified into the Trisagion frequently sung during services and said during prayers: "Holy God, Holy Mighty, Holy Immortal One, have mercy on us." The biblical use of "Holy" three times is an indication of the three Persons in the Godhead. (2) Memorial Service performed by the graveside or in church for the repose of the soul.