Fr. Stephen writes:
What is clear in Irenaeus’ teaching is that there was what he called the “Apostolic Hypothesis,” a framework of basic doctrine by which Scripture (first the Old Testament, later the New) should be interpreted. This consensus fidelium, or rule of faith, guided the Church century after century into its life, continually enlivened by the Holy Spirit. Though expressed in different ways at different times, the central goal was always the same: that the Church would teach the same Christ as it had received, and proclaim the same salvation it had always known.
The rest of the article is found here- read it!