The Early Church Fathers
Since, however, it would be very tedious, in such a volume as this, to reckon up the successions of all the Churches, we do put to confusion all those who, in whatever manner, whether by an evil self-pleasing, by vainglory, or by blindness and perverse opinion, assemble in unauthorized meetings, by indicating that tradition derived from the apostles, of the very great, the very ancient, and universally known Church founded and organized at Rome by the two most glorious apostles, Peter and Paul, as also the faith preached to men, which comes down to our time by means of the successions of the bishops. For it is a matter of necessity that every Church should agree with this Church, on account of its pre-eminent authority, that is, the faithful everywhere, inasmuch as the apostolical tradition has been preserved continuously by those who exist everywhere."
Irenaeus,Against Heresies,3:3:2 (A.D. 180),in ANF,I:1415-416
There are several important things to notice here. First, Irenaeus is not speaking of papal primacy. This is more than evidence by the fact that he has referred to both Peter and Paul as the founders of the church of Rome. Second, Irenaeus is ascribing authority to the teaching of the Roman church, not to the bishop of the Roman church. He reasons that since this particular church was founded by Peter and Paul, this is the church which preserves the teachings of Peter and Paul and it is upon that apostolic tradition that Rome has their authority. In other words, if the Roman church was not teaching the apostolic traditions passed down from bishop to bishop, he would not be making this statement. The succession he is discussing here is not a succession of official authority, but a succession of bishops who have preserved the apostolic teaching. Put another way, the validity of succession does not rest ulimately upon the authority of the office of bishop, but upon the authority of the apostolic teaching the bishop commissioned to preserve. The authority of a bishop is not in his office, but in the teaching of the apostles.