As we already have seen, the eucharistic Divine Liturgy is not celebrated in the Orthodox Church on lenten weekdays. In order for the faithful to sustain their lenten effort by participation in Holy Communion, the Liturgy of the Presanctified Gifts is served. The service is an ancient one in the Orthodox Church. We officially hear about it in the canons of the seventh century, which obviously indicates its development at a much earlier date.
On all days of the holy fast of Lent, except on the Sabbath, the Lord's Day, and the holy day of the Annunciation, the Liturgy of the Presanctified is to be served (Canon 52, Quinisext, 692).
The Liturgy of the Presanctified Gifts is an evening service. It is the solemn lenten Vespers with the administration of Holy Communion added to it. There is no consecration of the eucharistic gifts at the presanctified liturgy. Holy Communion is given from the eucharistic gifts sanctified on the previous Sunday at the celebration of the Divine Liturgy, unless, of course, the feast of the Annunciation should intervene; hence its name of "presanctified."
The Liturgy of the Presanctified Gifts is served on Wednesday and Friday evenings, although some churches may celebrate it only on one of these days. It comes in the evening after a day of spiritual preparation and total abstinence. The faithful who are unable to make the effort of total fasting because of weakness or work, however, normally eat a light lenten meal in the early morning.
During the psalms of Vespers, the presanctified gifts are prepared for communion. They are transferred from the altar table where they have been reserved since the Divine Liturgy, and are placed on the table of oblation. After the evening hymn, the Old Testamental scriptures of Genesis and Proverbs are read, between which the celebrant blesses the kneeling congregation with a lighted candle and the words: "The Light of Christ illumines all," indicating that all wisdom is given by Christ in the Church through the scriptures and sacraments. This blessing was originally directed primarily to the catechumens -- those preparing to be baptized on Easter -- who attended the service only to the time of the communion of the faithful.
After the readings, the evening Psalm 141 is solemnly sung once again with the offering of incense. Then, after the litanies of intercession and those at which the catechumens were dismissed in former days, the presanctified eucharistic gifts are brought to the altar in a solemn, silent procession. The song of the entrance calls the faithful to communion.
Now the heavenly powers (i.e., the angels) do minister invisibly with us. For behold the King of Glory enters. Behold the mystical sacrifice, all fulfilled, is ushered in.
Let us with faith and love draw near that we may be partakers of everlasting life. Alleluia. Alleluia. Alleluia.
After the litany and prayers, the Our Father is sung and the faithful receive Holy Communion to the chanting of the verse from Psalm 34: "O taste and see how good is the Lord. Alleluia." The post-communion hymns are sung and the faithful depart with a prayer to God who "has brought us to these all-holy days for the cleansing of carnal passions," that he will bless us "to fight the good fight, to accomplish the course of the fast, and to attain unto and to adore the holy resurrection" of Christ.
The Liturgy of the Presanctified Gifts is traditionally considered to be the work of the sixth-century pope, Saint Gregory of Rome. The present service, however, is obviously the inspired liturgical creation of Christian Byzantium.
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