With the emergence of the writings of Dionysius the Areopagite in the early sixth century, such as On the Ecclesiastical Hierarchy and On the Celestial Hierarchy, the Divine Liturgy was seen more and more as a participation in the eternal liturgy of heaven. The connection to the angelic liturgy, already present in the first century Book of Hebrews and articulated in the fourth century by John Chrysostom, found emphasis in the script for the Divine Liturgy in the years after the death of Emperor Justinian.
The addition of the Cherubic Hymn, or Cherubikon, to the Divine Liturgy in 573-74 under Patriarch John III Scholastikos (565-577) and Emperor Justin II (565–578) enhanced the impact of the eucharistic rite by pointing to heaven. It coincided with the introduction of the Great Entrance into the Divine Liturgy, when a separation of the room where the gifts are prepared from the room where they are consecrated made it necessary for a procession to take place. As an offertory hymn sung during the transfer of the bread and wine to the altar, the Cherubic Hymn invokes the eternal liturgy of the angels who encircle the throne of God:
We who mystically represent the Cherubim,
and who sing to the Life-Giving Trinity the thrice-holy hymn,
let us now lay aside all earthly cares
that we may receive the King of all,
escorted invisibly by the angelic orders.
Alleluia, Alleluia, Alleluia.
The congregation's "mystical representation" of the angels is not merely about role playing, but we truly inhabit the role, just as the Prophet Isaiah saw it in Isaiah 6:3. The Trisagion, or Thrice-Holy Hymn, had entered the Divine Liturgy, with some initial controversy, in the course of the fifth century. The addition of the new Cherubic Hymn composed by Patriarch John Scholastikos emphasized the point of singing the Trisagion. The Cherubikon made explicit what the performance of the angel's thrice-holy hymn left implicit, namely that those who sang the Trisagion joined themselves to the singing of the angels. Thus the faithful are granted the privilege of participating in the heavenly liturgy, joining themselves not to the biblical past, but to the eternal present in God's divine choir. This is further emphasized when considering the fact that the cleric processing with the Holy Gifts is escorted invisibly by the angelic orders, which is not meant to be a conjuring of the poetic imagination, but a true heavenly reality on earth.
Patriarch John III Scholastikos added another hymn/prayer to the Divine Liturgy, which is sung right before and during the communion of the faithful, known by its first words, Of Thy Secret Supper, though it was originally meant to be used only on Holy Thursday:
Of Thy Secret Supper, O Son of God, accept me today as a communicant; for I will not speak of Thy Mystery to Thine enemies, neither will I give Thee a kiss as did Judas; but like the thief will I confess Thee: Remember me, O Lord in Thy Kingdom.
These two hymns added around fifteen years after the death of Justinian, connect the faithful to the biblical past but most importantly draw them upward to heavenly realities through the liturgical performance. This is how the faithful are primarily called to participate in the Divine Liturgy.