authority of its teachers, which they exercised in the name of Christ, and by the power of the Holy Spirit continually attending upon their ministry, and attesting His presence as well by the perpetual operation of His grace as by the extraordinary and visible action of spiritual gifts. That authority was complete before the sacred writings of the New Testament were made public, and without their attestation. The authority divinely instituted[140] to preserve and propagate the doctrine preached by the Apostles was neither changed in character nor diminished by the writing of the books of the New Testament and by their delivery to the several churches. The proof of this is twofold. First, the nature of the teaching office itself, placed by Christ in the Apostles and their perpetual succession, to which He promised His own ever-abiding assistance, with the gift of the Holy Spirit dwelling in them. For these two things were not accidental or temporary, but the cause for ever of the Christian profession's continuance. Secondly, the consideration of all the circumstances which surround the writings themselves corroborates this conclusion. Before these books were written,[141] and much more before they were all collected and read in all churches, these churches themselves had been arranged by the teaching and ordering of the Apostles according to the charge they had received from Christ; bishops had been appointed in them by imposition of the Apostles' hands; the doctrine delivered to them by the Apostles had been committed to them as a deposit to be faithfully guarded through the gift of the Holy Spirit: they had been charged to appoint successors in every place, endowed with the like authority and the same gift. Thus the faithful everywhere depended, with the obedience of faith, upon the authority of the apostolic successors as God's messengers, from whom they were to receive Christian doctrine and discipline. This was not a mere dependence of those who were learning upon the knowledge of those who were teaching, because as yet there were no books from which each individual might learn for himself, but it was a proper office of teaching upon which the obedience of faith depended by Christ's institution, and by which the unity of the churches was maintained. When, therefore, inspired books containing revealed doctrine were gradually delivered by the Apostles to the churches, the ecclesiastical constitution already existing was not destroyed, but documents were added to be used in accordance with that constitution, to be preserved by those same bishops as successors of the Apostles and guardians of the deposit, and to be explained by them should doubt arise as to the meaning.