The Codex Amiatinus is the most celebrated manuscript of the Latin Vulgate Bible, remarkable as the best witness to the true text of St. Jerome and as a fine specimen of medieval calligraphy, now kept at Florence in the Bibliotheca Laurentiana . The symbol for it is written am or A (Wordsworth). It is preserved in an immense tome, measuring in height and breadth 19 1/4 inches by 13 3/8 inches, and in thickness 7 inches -- so impressive, as Hort says, as to fill the beholder with a feeling akin to awe. Some consider it, with White, as perhaps "the finest book in the world"; still there are several manuscripts which are as beautifully written and have besides, like the Book of Kells or Lindisfarne Gospels, those exquisite ornaments of which Amiatinus is devoid. It contains 1029 leaves of strong, smooth vellum, fresh-looking today, despite their great antiquity, arranged in quires of four sheets, or quaternions. It is written in uncial characters, large, clear, regular, and beautiful, two columns to a page, and 43 or 44 lines to a column. A little space is often left between words, but the writing is in general continuous. The text is divided into sections, which in the Gospels correspond closely to the Ammonian Sections . There are no marks of punctuation, but the skilled reader was guided into the sense by stichometric, or verse-like, arrangement into coda and commata, which correspond roughly to the principal and dependent clauses of a sentence. This manner of writing the scribe is believed to have modelled upon the great Bible of Cassiodorus , but it goes back perhaps even to St. Jerome.

Originally three copies of the bible were commissioned by Ceolfrid in 692. This date has been established as the monasteries at Wearmouth and Jarrow secured a grant of additional land to raise the 2000 head of cattle needed to produce the vellum. Bede was most likely involved in the compilation. Ceolfrid accompanied one copy destined for Rome but he died on route. The book later appears in the 9th Century at the Monastery of St Saviour's Amiata near Siena (hence "Amiatinus") where it remained until 1786 where it passed to the Laurentian Library. The dedication page had been altered and the librarian Angelo Maria Bandini claimed that the author was Severus a follower of St. Benedict and was produced at Monte Cassino around the 540s. This claim was accepted for the next hundred years establishing it as the oldest copy of the Vulgate but scholars in Germany noted the similarity to 9th Century texts. In 1888 G.B. Rossini established that the Codex was related to the bibles mentioned by Bede. This also established that Amiatinus was related to the Greenleaf Bible fragment in the British Library. Although Rossini's attribution removed 150 years from the age of the Codex it remained the oldest verson of the Vulgate. A 9th Century copy of the Codex Amiatinus is the personal bible of the Pope.