Calvin on Radical Individualism

Contrary to a modern mindset of some Evangelical Protestants, who change churches as one would change outfits to fit the caprice of fashion and weather, Calvin approached the issue of church fellowship with decidedly more caution:

Be this as it may, when the preaching of the gospel is reverently heard, and the sacraments are not neglected, there for the time the face of the Church appears without deception or ambiguity; and no man may with impunity spurn her authority, or reject her admonitions, or resist her counsels, or make sport of her censures, far less revolt from her, and violate her unity, (see Chap. 2 sec. 1, 10, and Chap. 3. sec. 12.) For such is the value which the Lord sets on the communion of his Church, that all who contumaciously alienate themselves from any Christian society, in which the true ministry of his word and sacraments is maintained, he regards as deserters of religion. So highly does he recommend her authority, that when it is violated he considers that his own authority is impaired.

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I admit, that it is a great disgrace if dogs and swine are admitted among the children of God; much more, if the sacred body of Christ is prostituted to them. And, indeed, when churches are well regulated, they will not bear the wicked in their bosom, nor will they admit the worthy and unworthy indiscriminately to that sacred feast. But because pastors are not always sedulously vigilant, are sometimes also more indulgent than they ought, or are prevented from acting so strictly as they could wish; the consequence is, that even the openly wicked are not always excluded from the fellowship of the saints. This I admit to be a vice, and I have no wish to extenuate it, seeing that Paul sharply rebukes it in the Corinthians. But although the Church fail in her duty, it does not therefore follow that every private individual is to decide the question of separation for himself. I deny not that it is the duty of a pious man to withdraw from all private intercourse with the wicked, and not entangle himself with them by any voluntary tie; but it is one thing to shun the society of the wicked, and another to renounce the communion of the Church through hatred of them. (Institutes, IV.i.10, 15)