We have learned from none others the plan of our salvation, than from those through whom the Gospel has come down to us, which they did at one time proclaim in public, and, at a later period, by the will of God, handed down to us in the Scriptures, to be the ground and pillar of our faith. For it is unlawful to assert that they preached before they possessed “perfect knowledge,” as some do even venture to say, boasting themselves as improvers of the apostles. For, after our Lord rose from the dead, [the apostles] were invested with power from on high when the Holy Spirit came down [upon them], were filled from all [His gifts], and had perfect knowledge
Irenaeus of Lyons, “Irenæus against Heresies,” III.1.1, in The Apostolic Fathers with Justin Martyr and Irenaeus, ed. Alexander Roberts, James Donaldson, and A. Cleveland Coxe, vol. 1, The Ante-Nicene Fathers (Buffalo, NY: Christian Literature Company, 1885), 414.