Such an attempt requires first an approximation of the date of its composition. Hanford argued half a century ago that Milton worked on the book from about 1655 to 1660, a conclusion that is still convincing. A brief review of the evidence will be useful. The fact that the manuscript is entirely in the handwriting of amanuenses suggests that it received its present form after Milton's final loss of vision early in 1652. Further evidence is the citation of a "recent" edition of the Bible in England, which Fletcher proved to be Walton's Polyglot of 1657. No other internal evidence seems to require a date later than this, though the reference to Walton's book does at least prove that Milton was occupied with this part of the treatise after 1657. How much later cannot be demonstrated from internal evidence, nor does it prove when he first began work on it.

External evidence is more helpful, supporting a date between about 1655 and a short time after 1660, the period when the anonymous biographer reports that Milton was "framing a Body of Divinity out of the Bible: All which, notwithstanding the several Calamities befalling him in his fortunes, he finish'd after the Restoration." But this activity seems to be the formal culmination of a lifetime of reflection on the Bible. Edward Phillips reports that in the early 1640s Milton's students were busy "writing from his own dictation, some part, from time to time, of a Tractate which he thought fit to collect from the ablest of Divines, who had written of that Subject; Amesius, Wollebius, &c. viz. A perfect System of Divinity." Milton himself testifies that even earlier as a youth he had carefully read the Old and New Testaments in the light of "a few of the shorter systems of divines" -- presumably such dogmatists as Ames and Wolleb-so as to extract textual proofs to be incorporated under various doctrinal headings (XIV, 5). A regular practice of Reformed dogmatists was such a compilation of proof texts for disputed points. Milton's subject headings probably derived from the "shorter systems" which he was studying, but the proof texts would mostly be his own collection, agreeing to a greater or lesser degree with those of the dogmatists. The results of such reading, which he seems to have carried on throughout most of his life, survive in the extensive collections of proof texts which fill the pages of the Christian Doctrine. Insertions in the manuscript of new proof texts by various hands show that he continued to consider them as long as he worked on the treatise. Wherever he cites clusters of proof texts without any analysis of them in the treatise, it appears that they have simply been added to his main running text, which reads meaningfully without any interruption if they are omitted. Such proof texts, that is, seem to have been inserted from a separate compilation after or during the composition of the running text.

It seems likely then that in his youth, guided by well-known Reformed dogmatists, Milton began an attempt to organize disparate biblical texts into some kind of theological outline, that throughout much of his adult life he continued to work on it, and that in the latter part of the 1650s he developed it from an outline collection of texts into its present state with the title, De doctrina christiana. If so, who were the readers of about 1655 to 1660 whom he wished to favor with a work which he considered to be his "best and richest possession" (XIV, 9)? Obviously, they had to be people of profound religious conviction, but even a cursory reading shows that it was not addressed to Catholics, Lutherans, or Anglicans. Rather, its imagined audience must have been men trained in the kind of theological analysis which the Christian Doctrine itself represents -- members of the various branches of the Reformed or Calvinistic churches. In England their most obvious representatives were the Presbyterians, who had controlled England from 1642 until Cromwell's purge of them from Parliament in 1648 and who were not a negligible group a decade later. . .