Expositio fidei catholiae
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Expositio Fidei
Wikipedia
Another complementary early reference is an exposition of faith published in 1883 by Carl Paul Caspari from the Ambrosian manuscript, which also contains the Muratorian (canon) fragment.
pater est Ingenitus, filius uero sine Initio genitus a patre est, spiritus autem sanctus processit a patre et accipit de filio, Sicut euangelista testatur quia scriptum est, "Tres sunt qui dicunt testimonium in caelo pater uerbum et spiritus:" et haec tria unum sunt in Christo lesu. Non tamen dixit "Unus est in Christo lesu."
Edgar Simmons Buchanan,[SUP][77][/SUP] points out that the reading "in Christo Iesu" is textually valuable, referencing 1 John 5:7.
The authorship is uncertain, however it is often placed around the same period as Priscillian. Karl Künstle saw the writing as anti-Priscillianist, which would have competing doctrinal positions utilizing the verse. Alan England Brooke [78] notes the similarities of the Expositio with the Priscillian form, and the Priscillian form with the Leon Palimpsest. Theodor Zahn [79] refers to the Expositio as "possibly contemporaneous" to Priscillian, "apparently taken from the proselyte Isaac (alias Ambrosiaster)".
John Chapman looked closely at these materials and the section in Liber Apologeticus around the Priscillian faith statement "Pater Deus, Filius, Deus, et Spiritus sanctus Deus ; haec unum sunt in Christo Iesu". Chapman saw an indication that Priscillian found himself bound to defend the comma by citing from the "Unity of the Church" Cyprian section.[80]
77 The Codex Muratorianus, Journal of Theological Studies, 1907 pp.537–545
78 Alan England Brooke, A critical and exegetical commentary on the Johannine epistles, 1912, pp.158–159
79 Theodor Zahn, Introduction to the New Testament, Vol 3, 1909, p. 372
80 "It seems plain that the passage of St, Cyprian was lying open before the Priscillianist author of the Creed (Priscillian himself?) because he was accustomed to appeal to it in the same way. In Priscillian's day St. Cyprian had a unique position as the one great Western Doctor." John Chapman, Notes on the Early History of the Vulgate Gospels, 1908, p.264
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Grantley - RGA - p. 37
The phrase unum sunt in Christo [lesu] subsequently occurs as a Trinitarian symbolum in two large-scale creeds. The first is the Reply to Pope Damasus, written in or before 384 (the year of Damasus’ death) by Priscillian or one of his followers.47 The second is the Expositio fidei chatolice, an orthodox creed written probably in Spain in the fifth or sixth century, in which this symbolum occurs as part of the wording of the Johannine comma.48
48 Expositio fidei chatolice, in Caspari, 1883, XIV, 305: “[...] pater est ingenitus, filius uero sine initio genitus a patre est, spiritus autem sanctus processet [procedit Caspari] a patre et accipit de filio sicut euangelista testatur, quia scriptum est: Tres sunt qui dicunt testimonium in caelo: pater, uerbum et spiritus, et hcec tria unum sunt in Christo lesu. Non tamen dixit: unus est in Christo lesu.” The Expositio is preserved in Milan, Biblioteca Ambrosiana ms I 101 sup., the same eighth-century manuscript that contains the Muratorian Canon. The date and provenance of the Expositio are disputed. Caspari, 1883, 304-308, the first editor of the document, suggested that it was written in Africa around the fifth or sixth century. Morin, 1899, 101-102, suggested less convincingly that it was written by Isaac Judaeus in the time of Pope Damasus (372). A more convincing explanation was offered by Kiinstle, 1905b, 89-99, who suggested that it was written in Spain in the fifth or sixth century against the position of Priscillian. In support of his contention that the Expositio is Spanish, Kiinstle noted that the same manuscript contains a Fides Athanasii, which is identical with the eighth chapter of the De Trinitate of ps.-Vigilius, and that the whole collection of documents in this manuscript is a suite of tracts belonging to the anti-Priscillianist movement. He concluded that Isaac cannot have written the Expositio, since he lived before the comma Johanneum is first attested, though this argument seems a little circular. Further on Morin’s hypotheses, see Lunn-Rockliffe, 2007, 33-62. It should be noted that the reading of the comma in Priscillian and in the Expositio is very similar to that later found in the biblical manuscripts Madrid, Complutense ms 31 and Le6n, Archivio catedralicio ms 6.
