Irenaeus’s summary of the biblical narrative reflects what was called the “rule of faith.” In the second century there were no creeds as such, but at baptism, catechumens—men and women who had been instructed in Christian teaching and were about to be received into the Church—were asked a set of three questions dealing with the Father, Son, and Holy Spirit. The “rule of faith” had a Trinitarian structure and identified God by events recorded in the Scriptures, the creation of the world, the call of Abraham, the coming of Christ in the flesh, and the sending of the Holy Spirit.
