No account of the first edition of Erasmus’s famous edition of the New Testament (1516) is complete without mentioning his treatment of the notorious Comma Johanneum: two half verses in 1 John 5:7–8 that speak of the Father, the Word, and the Holy Ghost as three witnesses in heaven who are one, and who are contrasted with the witnesses on earth. These are, as the remainder of verse 8 tells us, the Spirit, the Water, and the Blood, which agree in one. Anyone even only vaguely familiar with Christian theology will recognize that in the first half the Holy Trinity is mentioned, with the Word denoting Jesus, the Word incarnate. For centuries, these two half verses served as the most solid scriptural evidence of the doctrine of the Holy Trinity—a consubstantial Trinity united in essence. There are other passages in the Bible that might be recognized as referencing the Trinity, but none so explicitly as John’s First Epistle. Erasmus, however, omitted this comma from his edition because it did not appear in the Greek manuscripts on which he based his edition. The outcry he thus provoked is well recorded and well studied. In his third edition, Erasmus restored the comma on the basis of new manuscript evidence that, as on command, surfaced in England. Nevertheless, Erasmus maintained his doubts about its authenticity, as appears from his commentary. The comma sparked a controversy that abated only in the nineteenth century, with the professionalization of biblical philology, leading to a broad consensus that the comma is indeed spurious. However, as Grantley McDonald shows, nowadays there are still fundamentalist Christians who are convinced that the comma is authentic after all.

The first chapter of McDonald’s rich survey of the long history of the debate covers a story that has often been told before, but the author’s lucid accounts read fresh. Based on rereading all the primary material involved, including the multiple (and voluminous) polemics that evolved, McDonald manages to correct some inaccuracies in the general account, which has increasingly been worn out by sequences of secondary literature repeating and rephrasing each other without recourse to the primary sources. The most salient result is what he identifies as the “myth” or “legend” that Erasmus promised to restore the comma if he would be shown manuscript evidence of its authenticity. From the late seventeenth century onward, this version of the story served a variety of religious stakeholders.

McDonald has managed to maintain this thorough approach throughout the monograph. This is no small feat, as anyone who has ever tried to unpack the details of early modern learned polemics knows. In tit-for-tat pamphlet wars this is already notoriously complicated, but Erasmus fought against at least three adversaries, and their arguments were rehearsed by many different stakeholders over the next few centuries, often with the inclusion of new material. McDonald’s panoramic empirical survey includes not only the controversialists and their textual arguments, uncovered from the thickets of rhetorical layers, but also the history of the printed editions, as the second chapter on sixteenth-century Bibles evidences: Greek, Latin, and even the Peshitta and Arabic editions are analyzed with painstaking detail, as well as the responses of various Protestant denominations. McDonald maintains this survey to the end of his book, when the reader finds herself in the company of Lachmann.

In a way, McDonald pays tribute to Erasmus’s methods by sticking so closely to textual evidence. But by having one’s nose so close to the sources, and with so much repetition of the arguments by the historical actors, the reader at some point starts to feel satiated. Well aware, McDonald intermittently zooms out to add a signpost to his text and he ends all his chapters with useful synopses. To some, a drawback might be the preponderance of seventeenth-century English biblical scholars treated. The textual accomplishments of scholars in the early German Enlightenment are not ignored, but the rest of the European mainland is largely left out of the picture, despite the wide-ranging geography of McDonald’s account of sixteenth-century editions. Still, the author has drawn an astonishing history of the multiple responses to defenses, negotiations, or rejections of the Comma Johanneum. What this book superbly demonstrates is that the relation between philology and theology is by no means straightforward, and that there was by no means a clash between philology and theology.