Sacramentarium Gelasianum

The so-called Gelasian Sacramentary (Latin: Sacramentarium Gelasianum) is a book of Christian liturgy, containing the priest's part in celebrating the Eucharist. It is the second oldest western liturgical book that has survived: only the Verona Sacramentary is older.

The book exists in several manuscripts, the oldest of which is an 8th-century manuscript in the Vatican Library, acquired from the library of Queen Christina of Sweden (thus MS Reginensis 316); in German scholarship this is referred to as the Altgelasianum, and is considered the sacramentary used by Saint Boniface in his mid-8th century mission on the European continent. This is the most important surviving Merovingian illuminated manuscript, and shows a synthesis of Late Antique conventions with "barbarian" migration period art motifs comparable to the better known insular art of Britain and Ireland.

In none of its old manuscripts does the book bear the name of Gelasius but is simply called Liber sacramentorum Romanae ecclesiae ("Book of Sacraments of the Church of Rome"). However, an old tradition linked the book to Pope Gelasius I, apparently based on Walafrid Strabo's ascription of what is evidently this book to the 5th-century pope. The sacramentary was compiled near Paris around 750, and it contains a mixture of Gallican and Roman elements [1]. The dating of the liturgical contents are not based on characteristics of the surviving manuscript itself (ca 750): most of its liturgy reflects the mix of Roman and Gallican practice inherited from the Merovingian church. In 785-6 the reforms of Pope Gregory I, Gregory the Great, were supplied to Charlemagne by Pope Hadrian I. The spurious ascription to Gelasius gave an added authority to the contents, which are an important document of pre-Gregorian liturgy.

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