Same old, same old: A plethora of Christian churches teaching widely varying “truths”.

In his famous work Against the Heresies Irenaeus–the saintly Bishop of Lyon wrote about all the different little groups who made claims to authenticity and gave them a sure fire way of knowing the truth:

“It is possible, then, for everyone in every church, who may wish to know the truth, to contemplate the tradition of the apostles which has been made known throughout the whole world. And we are in a position to enumerate those who were instituted bishops by the apostles and their successors to our own times—men who neither knew nor taught anything like these heretics rave about.

“But since it would be too long to enumerate in such a volume as this the successions of all the churches, we shall confound all those who, in whatever manner, whether through self-satisfaction or vainglory, or through blindness and wicked opinion, assemble other than where it is proper, by pointing out here the successions of the bishops of the greatest and most ancient church known to all, founded and organized at Rome by the two most glorious apostles, Peter and Paul, that church which has the tradition and the faith which comes down to us after having been announced to men by the apostles.”
“With this church, because of its superior origin, all churches must agree—that is, all the faithful in the whole world—and it is in her that the faithful everywhere have maintained the apostolic tradition”
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