170AD Irenaeus, Against Heresies 3.2 - Heretics allege truth was delivered not by written documents, but by oral tradition. Without this oral tradition you can't properly interpret the Scriptures.
170AD Irenaeus, Against Heresies 3.3 - The Apostles did not pass down any hidden wisdom, just the scriptures. If an older written document contradicts the newer written document we believe the older.
170AD Irenaeus, Against Heresies 4.26 - Obey the presbyters who are in the Church,--those who possess the succession from the apostles; together with the succession of the episcopate, who have received the certain gift of truth. But it is also incumbent to hold in suspicion others who depart from the primitive succession. Avoid all who do not hold to the doctrine of the Apostles, including Presbyters.
170AD Irenaeus, Against Heresies 4.33 - The doctrine of the apostles, has been guarded and preserved without any forging of Scriptures, as a very complete system of doctrine. Neither receive addition to or suffer curtailment from its truths. Read the word of God without falsification, lawfully and diligently explaining them in harmony with the rest of the Scriptures.
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