The date of this treatise is the subject of controversy. In §1 Jerome says that he wrote “after three years,” that is, three years from the visit of Epiphanius to Jerusalem, which was in 394. This would give the date 397. At §14, also, he says that Epiphanius had been brooding over his wrongs for three years. Another note of time is found in the words of §43, that John had “lately” sought to obtain a sentence of exile against Jerome from “that wild beast who threatened the necks of the whole world,” that is, the Prefect Rufinus, who died at the end of 395. All these statements point to the year 397. On the other hand, at §17, he speaks of his “Commentaries” on Ecclesiastes and Ephesians as having been written “about (ferme) ten years ago”; and the preface to Ecclesiastes says that he had read Ecclesiastes with Blesilla at Rome “about (ferme) five years ago,” consequently, fifteen years before the writing of this treatise. Blesilla’s death was in 384. The reading of Ecclesiastes may, therefore, have been in 383. And the fifteen years would bring us to 398. Also, at §41, Jerome says, addressing John. “You seem to have slept for thirteen years,” implying that it was for thirteen years that the state of things complained of by John had existed, that is, the presence of the monks in his diocese, or, at least, their leaving their own dioceses. Jerome left Antioch, the diocese of his ordination, at the end of 385 or beginning of 386; these thirteen years, therefore, bring us to 399, the date adopted by Vallarsi. There is, however, an intimation in “Pallad. Hist. Laus.,” c. 117, that Melania, the friend of Rufinus, gave assistance in the matter of “the schism of nearly 400 monks who followed Paulinus,” which is admitted to relate to the schism at Bethlehem, caused by the question of the ordination of Paulinianus. We know that Melania and Rufinus left Jerusalem early in 397, and that, before their departure, Jerome and Rufinus were reconciled. It would, therefore, seem most probable that the treatise, which is written with so much animosity against John, Rufinus’s fellow-worker, and contains invidious allusions to Rufinus himself (§11, “your friends, who grin like dogs and turn up their noses,” Jerome’s constant description of Rufinus), was written before the reconciliation of Rufinus and Jerome, that is, in the end of 386 or the beginning of 387, and that it was broken off and kept unpublished because the situation had changed. Vallarsi places it in 399. He quotes the passages which make for the later date, but strangely omits the more definite statements which make for the earlier. It should be added that the letter of Jerome (LXXXII.) to Theophilus is evidently written at the same time, and under the same feelings, as this treatise. and, if the arguments above given are valid, that letter must be placed in 397, not in 399, as stated in the note prefixed to it. The short letter (LXXXVI.) to Theophilus is, in that case, probably to be placed in 398 or 399, rather than 401, as there stated.