COMMA JOHANNEUM. - A celebrated verse inserted in the First Epistle of St. John as one of the classic texts for establishing the distinction of the Persons of the Holy Trinity and the unity of the divine Substance: "There are three that bear witness in heaven, the Father, the Word, and the Holy Spirit, and these three are one. And there are three that bear witness on earth, the Spirit, the water, and the blood, and these three are one" (1 Jn 5:7).
I. THE PROBLEM
Its authenticity, long accepted on the basis of the "received Greek text" and the Vulgate, is today universally rejected. No modern critical edition of the Greek text, whether Protestant (Nestle) or Catholic (Vogels, Merk, Bover), contains II. The controversy began with the first two editions of Erasmus’ New Testament, which omitted it; it continued among Protestants until the mid-19th century and among Catholics until the early 20th century. As the dispute intensified, the Holy Office declared that its authenticity could neither be entirely denied nor placed in doubt (AAS, 29 [1897], p. 637). However, to avoid overly strict interpretations, the Church, through unofficial declarations issued shortly after the decree, through her adopted practice, and especially through the official interpretation given on June 2, 1927 (Enchiridion Biblicum, no. 121), made clear that she did not intend to close the controversy or prevent Catholic exegetes from continuing their research or even inclining toward a negative solution.II. THE FACTS
The Johannine comma, unknown in Greek manuscripts except for three (from the 16th century and influenced by the Vulgate), unknown to the Greek Fathers—who would have had many occasions to use it in Trinitarian controversies—and even unknown to those who commented on 1 John, and finally unknown to the Eastern versions, appeared only in the Latin West and at a relatively late period.The ancient Latin Fathers do not know it: Hilary, Ambrose, Augustine, Jerome, Leo the Great, and even in the 8th century, St. Bede, despite commenting on the entire epistle. The allusions detected in some writers such as Tertullian and especially Cyprian are explained by the fact that V. 8 was interpreted in a Trinitarian sense. The same can be said of Potamius of Lisbon (c. 350). Similarly, the manuscripts of the Old Latin version (all the fragments from Freising, 7th century, and a Paris codex from the 13th century that practically reproduces the Vulgate text) ignore II. It is found only from the 4th century onward, localized in Spain, and in forms quite divergent from one another, sometimes heterodox.
In the Vulgate, where it was accredited by the apocryphal prologue to the Catholic Epistles, composed, it seems, for this purpose, it is clearly of secondary origin. In fact, all the oldest texts omit it; up to the 11th–12th centuries, it is contained only in some manuscripts of Spanish origin or influence. With good reason, the Anglican editor White omits it (minor edition, 1911), and Merk, although retaining the text of the Sixtine-Clementine, indicates the omission as the preferable reading (4th ed., 1942).
III. ORIGIN OF THE COMM A
It is highly probable that the Johannine comma owes its origin to the Trinitarian interpretation of V. 8 (three earthly witnesses), as, for example, in St. Augustine’s *Contra Maximinum* (PL 42, 794).Indeed, in the oldest witnesses up to the 11th century, it is found inscribed after V. 8, as an explanation of that verse. The gloss, probably marginal in origin, must have passed into the text in some manuscripts of the Old Latin in Spain or perhaps in Africa, in any case before Priscillian or the author of the *Liber Apologeticus* (c. 380, ed. Schepss, CSEL, XVIII, p. 6); this work seems to cite the Johannine comma as an accepted text, and on this point was not attacked by its adversaries.