The so-called Decretum Gelasianum or the Gelasian Decree was traditionally attributed to the prolific Pope Gelasius I, bishop of Rome 492–496. In surviving manuscripts the Decretal exists on its own and also appended to a list of books of Scripture titled as attested as canonical by a Council of Rome under Pope Damasus I, bishop of Rome 366–383. Since that list contains a quotation from Augustine, writing about 416, it is evident that the title Incipit Concilium Vrbis Romae sub Damaso Papa de Explanatione Fidei, the so-called Damasine List, is of no historical value, although the canon presented herein represents the same canon as shown in the Council of Carthage Canon 24, 415 AD 
The Decretal include a list of works adjudged apocryphal "by Pope Gelasius and seventy most erudite bishops." Though the ascriptions are generally agreed to be apocryphal themselves, except among the most traditional of apologists, perhaps reflecting the seventy translators of the Septuagint and the seventy apostles sent out in Luke, this list de libris recipiendis et non recipiendis ("of books to be admitted and not to be admitted"), probably originating in the 6th century, represents a tradition that can be traced back to Pope Damasus I and reflects Roman practice in the development of the Biblical canon. In the list of gospels, the order is given as Matthew, Mark, Luke, John. Fourteen epistles are credited to Paul including Philemon and Hebrews. Of the General Epistles seven are accepted: two of Peter, one of James, one of the apostle John, two of "the other John the elder" (presbyter), and one of "Judas the Zealot".
The Decretum is in several parts: the second part is a canon catalogue, and the fifth part is a catalogue of the 'apocrypha' and other writings which are to be rejected. These apocrypha are not the same as the Deuterocanonical Books, but include the Acts of Andrew and other spurious works. The Deuterocanonical Books are accepted by the catalogue, and are still found in the Roman Catholic Bible, though not in the Protestant canon. The canon catalogue gives 27 books of the New Testament (Parts 1, 3, and 4 are not relevant to the canon.)
- The Development of the Canon": Decretum Gelasianum gives the full list, including the apocrypha "which are to be avoided by Catholics."
- Decretum Gelasianum: at The Latin Library.
- Decretum Gelasianum: in English.
- Review of Ernst von Dobschütz, Das Decretum Gelasianum de libris recipiendis et non recipiendis in kritischem Text Leipzig, 1912: F. C. Burkitt in Journal of Theological Studies 14 (1913) pp. 469–471.