Calvin on the Necessity of Reading and Hearing of God's Word

2. Hence it is easy to understand that we must give diligent heed both to the reading and hearing of Scripture, if we would obtain any benefit from the Spirit of God (just as Peter praises those who attentively study the doctrine of the prophets (2 Pet. 1:19), though it might have been thought to be superseded after the gospel light arose), and, on the contrary, that any spirit which passes by the wisdom of God’s Word, and suggests any other doctrine, is deservedly suspected of vanity and falsehood. Since Satan transforms himself into an angel of light, what authority can the Spirit have with us if he be not ascertained by an infallible mark? And assuredly he is pointed out to us by the Lord with sufficient clearness; but these miserable men err as if bent on their own destruction, while they seek the Spirit from themselves rather than from Him.

Calvin, J. (1997). Institutes of the Christian religion. Bellingham, WA: Logos Research Systems, Inc.