No earlier than about A.D. 64, Peter's Second Epistle (1:16-21) insists: "We have not followed cunning-devised fables! We made known to you the power and coming of our Lord Jesus Christ and were eyewitnesses of His majesty…. We heard!…. [Yet,] we have too a more sure word of prophecy…. Know this — that no forthtelling of the Scripture is from any private interpretation! For the forthtelling did not in olden times come by the will of man. But holy men of God spoke as they were moved by the Holy Ghost."
Here, Calvin comments (Epistles of St. Peter, Eerdmans’s ed., pp. 337-44): "Peter declares that he was an eyewitness, because he has seen with his own eyes the glory of Christ which he describes. He contrasts this knowledge with the kind of cunningly-devised fables which astute men are in the habit of inventing to entangle the minds of the simple…. What is meant, is a subtle invention with intent to deceive….
"'We have the Word of Prophecy made more sure…. No Scripture is of private interpretation! For no prophecy of Scripture ever came by the will of man. But men spake from God, being moved by the Holy Ghost'…. He [Peter] now goes on to show that the certainty of the Gospel is also based on the saying of the Prophets [as recorded in Holy Scripture]….
"The Papists are always saying that the Church cannot err…. They imagine that it is ruled by the Spirit, even though the Word has been lost! But Peter, on the contrary, declares that all are immersed in darkness, who do not look to the light of the Word. Therefore, unless you want to cast yourself of your own accord into a labyrinth – you must take the utmost care not to deviate even a hair’s breadth from the direction of the Word. Even the Church can follow only God as its Guide….
"It is worth noticing further what he [Peter] says about the clarity of Scripture. This would be a false commendation, if Scripture were not a fit and proper guide to show us the way clearly. Therefore, anyone who opens his eyes by the obedience of faith — will see, by that very experience, that Scripture has not for nothing been called a lamp…. It is therefore a damnable blasphemy of the Papists to imagine that the light of Scripture does nothing but dazzle the eyes — so that they frighten off the simple from reading it….
"Peter begins to show here how we ought to dispose our minds, if we want to make proper use of Scripture…. We ought not to rush at our reading of Scripture rashly, trusting in our own understanding….
"The Spirit Who spoke by the Prophets, is His Own True Interpreter. This exposition certainly contains a true, godly, and profitable lesson…. The Prophets are only read with advantage, when we put aside our carnal understanding and subject ourselves to the teaching of the Holy Spirit…. It is an unholy profanation of Scripture, when we presumptuously bring our own native shrewdness to the understanding of it….
"The Papists are doubly stupid in concluding from this, that no interpretation of private individuals ought to be looked on as authentic. They pervert this testimony of Peter, to arrogate to their councils the final authority to interpret Scripture. And in so doing, they act childishly indeed.
"Peter speaks of 'private interpretation' – not to prohibit any individual from handling Scripture by himself. But he is saying that whatever men bring to it of their own, is profane…. The faithful are enlightened by the Holy Spirit – and acknowledge only what God wills in His Word….