Quotes from The Institutes of the Christian Religion

Institutes of the Christian Religion was written as an introductory textbook on the Protestant faith for those with some previous knowledge of theology and covered a broad range of theological topics from the doctrines of church and sacraments to justification by faith alone and Christian liberty. It vigorously attacked the teachings of those Calvin considered unorthodox, particularly Roman Catholicism to which Calvin says he had been "strongly devoted" before his conversion to Protestantism. The Institutes is a highly regarded reference for the system of doctrine adopted by the Reformed churches, usually called Calvinism.

The Spirit Does Not Contradict the Gospel

But in promising it, of what sort did he declare his Spirit would be? One that would speak not from himself but would suggest to and instill into their minds what he had handed on through the Word [John 16:13]. Therefore the Spirit, promised to us, has not the task of inventing new and unheard-of revelations, or of forging a new kind of doctrine, to lead us away from the received doctrine of the gospel, but of sealing our minds with that very doctrine which is commended by the gospel. ~ Institutes of the Christian Religion

Forsaking Scripture, Men are Carried Away with Frenzy

Furthermore, those who, having forsaken Scripture, imagine some way or other of reaching God, ought to be thought of as not so much gripped by error as carried away with frenzy. For of late, certain giddy men have arisen who, with great haughtiness exalting the teaching office of the Spirit, despise all reading and laugh at the simplicity of those who, as they express it, still follow the dead and killing letter. ~ Institutes of the Christian Religion

Fictitious Worship

“Those who set up a fictitious worship, merely worship and adore their own delirious fancies; indeed, they would never dare so to trifle with God, had they not previously fashioned him after their own childish conceits.” ~ Institutes of the Christian Religion

Hidden Sins are not Less Heinous

“In forming an estimate of sins, we are often imposed upon by imagining that the more hidden the less heinous they are.” ~ Institutes of the Christian Religion

True Religion Must be According to God’s Will

“In a way, the futile excuses many people use to cover their superstitions are demolished. They think it is enough to have some sort of religious fervor, however ridiculous, not realizing that true religion must be according to God’s will as the perfect measure – that He can never deny Himself and is no mere spirit form to be changed around according to individual preference.” ~ Institutes of the Christian Religion

Sacraments without Faith

“For what is a sacrament received without faith, but most certain destruction to the church?” ~ Institutes of the Christian Religion 4.14.14