Calvin effectively argues against this "most pernicious error" in sections 1-3 of Book I, chapter 7. It is an arrogant position to take, that the church somehow, which is instituted in God's word, governed by God's word, and led by God's word, has the primacy when conflict arises between churchly practice and the plain Word of God.
When that which is set forth is acknowledged to be the Word of God, there is no one so deplorably insolent-unless devoid also both of common sense and of humanity itself-as to dare impugn the credibility of Him who speaks. (p. 74, Institutes of the Christian Religion)Yet the church who opposed Calvin and his teaching did -
But a most pernicious error widely prevails that Scripture has only so much weight as is conceded to it by the consent of the church. As if the eternal and inviolable truth of God depended upon the decision of men!Rather, the apostle Paul himself speaks with great clarity in Ephesians 2:20, when he declares plainly that the church is grounded "upon the foundation of the prophets and apostles". We have no commandments outside of Scripture which declare to us how the church is to be organized, and how the authority structures within are to be arranged - how we are to worship, and what we are to be dedicated to. Of human invention are many errors - yet Scripture plainly tells us what we are to be about in the church - and has ultimate authority over the church in worship, faith and practice. Calvin continues,
Again, to what mockeries of the impious is our faith subjected, into what suspicion has it fallen among all men, if we believe that it has a precarious authority dependent solely upon the good pleasure of men! (p. 75, Institutes of the Christian Religion)
But such wranglers are neatly refuted by just one word of the apostle. He testifies that the church is "built upon the foundation of the prophets and apostles" [Eph. 2:20]. If the teaching of the prophets and apostles is the foundation, this must have had authority before the church began to exist. Groundless, too, is their subtle objection that, although the church took its beginning here, the writings to be attributed to the prophets and apostles nevertheless remain in doubt until decided by the church. For if the Christian church was from the beginning founded upon the writings of the prophets and the preaching of the apostles, wherever this doctrine is found, the acceptance of it-without which the church itself would never have existed-must certainly have preceded the church. It is utterly vain, then, to pretend that the power of judging Scripture so lies with the church that its certainty depends upon churchly assent. Thus, while the church receives and gives its seal of approval to the Scriptures, it does not thereby render authentic what is otherwise doubtful or controversial. But because the church recognizes Scripture to be the truth of its own God, as a pious duty it unhesitatingly venerates Scripture. (p. 75-76, Institutes of the Christian Religion)Thank God the Scriptures undergird the church's practice, and govern all. Thank God for Paul, who wrote clearly, instructing us to search the Scriptures and study them in order to seek authenticity in a man's teaching - even his. Thanks be to God for the inestimable gift to us of His Holy Word.