Liturgy of Addai and Mari

The Liturgy of Addai and Mari is a Divine Liturgy belonging to the East Syrian Rite, which is in regular use, even if in different versions, in the Assyrian Church of the East and Ancient Church of the East, the Syro-Malabar Catholic Church and the Chaldean Catholic Church.

The anaphora or Eucharistic Prayer that is part of this liturgy is of particular interest, being one of the oldest in Christianity, possibly dating back to 3rd-century Edessa, even if the outline of the current form can be traced as far back only as the time of the Patriarch Mar Isho-Yab III in the 7th century. This liturgy is traditionally attributed to Saint Addai (disciple of Saint Thomas the Apostle) and Saint Mari (a disciple of Saint Addai). In the form given in the oldest manuscripts, all of the High Middle Ages, this anaphora does not include the Words of Institution, a matter that raised ecumenical concerns.

The Liturgy of Addai and Mari has been in continuous use in the Church of the East since at least the 7th century Hymns by Saint Ephrem and others are often sung during the communion. A piece of dough from the eucharistic bread is saved from week to week, not as reserve sacrament but as leaven for the next week's bread. Authors from Theodore of Mopsuestia (c. 400) to Mar Eshai Shimun XXIII in the mid-20th century and Mar Aprem Mooken of India in the early 21st century have identified the Epiclesis, beginning with the words Neethi Mar Rukhada Kudisha... (May the Holy Spirit come...) as the high point of the Holy Qurbana.

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