Polyeleos

The Polyeleos (Greek: Πολυέλεος (pl. Πολυέλεοι), meaning "of much mercy", because of the repetition in one of the Polyeleoi of the phrase "ὅτι εἰς τὸν αἰῶνα τὸ ἔλεος αὐτοῦ", meaning "because forever [lasts] His mercy"), is a festive portion of the Matins or All-Night Vigil service as observed on higher-ranking feast days in the Eastern Orthodox and Byzantine Rite Catholic Churches. The Polyeleos is considered to be the high point of the service, and contains the reading of the Matins Gospel. Because of its liturgical importance, beautiful settings for the Polyeleos have been composed by Sergei Rachmaninoff and others.

Specifically, the Polyeleos consists of Psalms 134 and 135 (Septuagint numbering; King James Version: Psalms and ), which are solemnly chanted in a festive melody, with refrains Alleluia chanted between each verse. The refrain for Psalm 134 is "Alleluia.". The refrain for Psalm 135 is "Alleluia, alleluia. For His mercy endureth forever. Alleluia." This repeated chanting of the word "mercy" is another reason for the chanting of these psalms to be called Polyeleos.

In its fullest musical setting, it can last up to over an hour. Nowadays, the psalms are usually shortened to only a few select verses each, except in certain monasteries.

During the chanting, Holy Doors are opened, and the clergy come out of the sanctuary to stand in front of the icon of the feast, which lies on an analogion in the center of the nave. The deacon (or priest, if there is no deacon) censes the icon of the feast being celebrated. However, if it is a Sunday service, the Holy Doors are opened, the clergy remain in the sanctuary and the priest censes the front of the Holy Table (altar).

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