Eusebian Canons

Until the 19th century it was mostly believed that these divisions were devised by Ammonius of Alexandria, at the beginning of the 3rd century (c. 220), in connection with a Harmony of the Gospels, now lost, which he composed. It was traditionally believed that he divided the four Gospels into small numbered sections, which were similar in content where the narratives are parallel. He then wrote the sections of the three last Gospels, or simply the section numbers with the name of the respective evangelist, in parallel columns opposite the corresponding sections of the Gospel of Matthew, which he had chosen as the basis of his gospel harmony. It is now believed that the work of Ammonius was restricted to what Eusebius of Caesarea (265-340) states concerning it in his letter to Carpianus, namely, that he placed the parallel passages of the last three Gospels alongside the text of Matthew, and the sections traditionally credited to Ammonius are now ascribed to Eusebius, who was always credited with the final form of the tables.

An Armenian illuminated manuscript of a canon table by Toros Roslin (active 1256 - 1268) entitled Canon Table Page.

Canon quartus in quo III from the Cutbercht Gospels (8th century, Salzburg)

The harmony of Ammonius suggested to Eusebius, as he says in his letter, the idea of drawing up ten tables (kanones) in which the sections in question were so classified as to show at a glance where each Gospel agreed with or differed from the others. In the first nine tables he placed in parallel columns the numbers of the sections common to the four, or three, or two, evangelists; namely: (1) Matt., Mark, Luke, John; (2) Matt., Mark, Luke; (3) Matt., Luke, John; (4) Matt., Mark, John; (5) Matt., Luke; (6) Matt., Mark; (7) Matt., John; (8) Luke, Mark; (9) Luke, John. In the tenth he noted successively the sections special to each evangelist. Sections "Mark, Luke, John" and "Mark, John" are absent because no text is common to Mark and John without a parallel in at least Matthew.

The usefulness of these tables for the purpose of reference and comparison soon brought them into common use, and from the 5th century the Ammonian sections, with references to the Eusebian tables, were indicated in the margin of the manuscripts. Opposite each section was written its number, and underneath this the number of the Eusebian table to be consulted in order to find the parallel texts or text; a reference to the tenth table would show that this section was proper to that evangelist. These marginal notes are reproduced in several editions of Tischendorf's New Testament.

Eusebius's explanatory letter to Carpianus was also very often reproduced before the tables.

The tables themselves were usually placed at the start of a Gospel Book; in illuminated works they were placed in round-headed arcade-like frames, of which the general form remained remarkably consistent through to the Romanesque period. This form was derived from Late Antique book-painting frames like those in the Chronography of 354. In many examples the tables are the only decoration in the whole book, perhaps other than some initials. In particular, canon tables, with Evangelist portraits, are very important for the study of the development of manuscript painting in the earliest part of the Early Medieval period, where very few manuscripts survive, and even the most decorated of those have fewer pages illuminated than was the case later.

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  Eusebian tables before text of the Gospels in Codex Harleianus 5567 (Gregory-Aland 116; 12th century)
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  One of the canon tables from the 8th century Codex Beneventanus.
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  The London Canon Tables are two folios from a Byzantine manuscript of the 6th or 7th century, showing the typical arcaded frame.

• Chronicon (Eusebius)

•  This article incorporates text from a publication now in the public domain: Herbermann, Charles, ed. (1913). "Ammonian Sections". Catholic Encyclopedia. New York: Robert Appleton Company.

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