The only one of these—“that furnished posterity with means of defense against heresies”—whom Eusebius mentions is Agrippa Castor, and it is evident that he knew of no others. Moreover, it is more than doubtful whether Agrippa Castor belonged to that time. We do not know when he wrote, but it is hardly possible that the Church had at that period any one capable of answering such a work as the Commentary of Basilides, or any one who would wish to if he could. The activity of the Church was at this early period devoted chiefly if not wholly to the production of apologies for the defense of the Church against the attacks of enemies from the outside, and to the composition of apocalypses. Eusebius in the next chapter mentions Hegesippus as another of these “writers of the time.” But the passage which he quotes to prove that Hegesippus wrote then only proves that the events mentioned took place during his lifetime, and not necessarily within forty or fifty years of the time at which he was writing. The fact is, that Hegesippus really wrote about 175 a.d. (later therefore than Justin Martyr), and in chap. 21 of this book Eusebius restores him to his proper chronological place. The general statement made here by Eusebius in regard to the writers against heresy during the reign of Hadrian rest upon his preconceived idea of what must have been the case. If the devil raised up enemies against the truth, the Church must certainly have had at the same time defenders to meet them. It is a simple example of well-meaning subjective reconstruction. He had the work of Agrippa Castor before him, and undoubtedly believed that he lived at the time stated (which indeed we cannot absolutely deny), and believed, moreover, that other similar writers, whose names he did not know, lived at the same time.