The Church
The churches could name their bishops back to the apostles, and used that to show where the true teaching was kept.
The apostolic plan stands revealed throughout the whole world; it is present for all who wish to see the truth to behold in every church. We can enumerate those whom the apostles instituted as bishops in the churches, along with their successions down to us — men who taught nothing of the kind, nor knew it, the very…
They insisted that the men they were leaving behind as successors be thoroughly blameless and irreproachable in every respect, so that great benefit would come to those who would act in their place of teaching, while the greatest calamity would befall those who fell away.
Clement had seen the Apostles themselves and conversed with them; he still had the Apostles' preaching and tradition before his eyes, for many who had been taught by the Apostles were still surviving at that time.
On this account we must avoid them, but we must love and cling to the things that belong to the Church with the greatest diligence, laying hold of the tradition of the truth.
If that is how it stands, then it follows that any doctrine which agrees with those apostolic churches — the matrices and originals of the faith — is to be counted as true, beyond doubt holding what the Churches received from the Apostles, the Apostles from Christ, Christ from God.
If anyone dares to wedge themselves into the apostolic era just so they can claim the Apostles handed them down—on the grounds that they ‘lived under the Apostles’—we can answer bluntly: let them cough up the origins of their churches.