A solis ortus cardine

"A solis ortus cardine" (From the hinge of the rising sun) is a Latin poem by Coelius Sedulius (died c. 450), recounting Christ's life from his birth to his resurrection. Its 23 verses each begin with a consecutive letter of the Latin alphabet, making the poem an abecedarius. It is one of the oldest parts of the Roman Catholic liturgy, with two hymns formed from the first seven and four later verses. There have been monastic translations into Anglo-Saxon and later translations into other languages, most notably the German versification of Martin Luther during the Reformation. The original Latin hymn and Luther's translation have been set for chorus and organ by many composers including Dufay, di Lasso, Praetorius, Palestrina, Scheidt, de Grigny and Bach.

A solis ortus cardine is a Latin hymn, written in the first half of the fifth century by the early Christian poet Sedulius. The abecedarius recounts in 23 quatrains of iambic dimeter the nativity, miracles and passion of Christ. With the other Latin texts of Sedulius, it enjoyed wide circulation in the church and in schools from late antiquity and medieval times until the end of the seventeenth century. The opening words are cited by Bede in his De Arte Metrica and were used without reference by medieval poets; and the seventeenth verse Rivos cruoris torridi, describing Christ's miraculous healing of the bleeding woman, was even proffered as a medieval charm against bleeding.

The first seven verses, with a doxology verse by a different writer, were used from the early Middle Ages onwards as a Christmas hymn. They write of the striking contrast between the grandeur and omnipotence of the Word of God (the second person in the Trinity) and the vulnerable humanity of the child in whom the Word became flesh. In 1589 Palestrina set the odd verses (A,C,E,G) in Hymni totius anni secundum Sanctae Romanae Ecclesiae consuetudinem, necnon hymni religionum, a collection of hymns composed for the Vatican; liturgical practice was for the even verses to be sung in Gregorian plainchant.

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