The most integral part of Christian worship is the Holy Mass, where the church comes together to enjoin as one in the Sacrament of Christ's Body and Blood. This is universal throughout Christianity, where its practice is detailed in liturgical books according to church tradition. The Aifreann na hEireann, or ""Irish Mass,"" is a faithful translation and reconstruction of the Lorrha Missal, the oldest surviving liturgical text in Ireland. Each chapter is a complete liturgy, including rubrics for clerical use. Combined with the Portus na hEireann, these books serve as a complete liturgical rite that allows Christians to worship in the manner of early Irish monks.
