The names of the persons to whom this epistle was addressed we do not know, nor can we ascertain the exact time when it was composed, though it must have been written before Heraclas became bishop of Alexandria, and indeed, we may assume, while Origen was in Alexandria, and still engaged in the study which he defends in the epistle, i.e., if Eusebius is correct in the order of events, before 216 a.d. (see note 23).