John Calvin: We have laid down as distinguishing marks of the church the preaching of the Word and the observance of the sacraments. These can never exist without bringing forth fruit and prospering by God’s blessing. I do not say that wherever the Word is preached there will be immediate fruit; but wherever it is received and has a fixed abode, it shows its effectiveness. However it may be, where the preaching of the gospel is reverently heard and the sacraments are not neglected, there for the time being no deceitful or ambiguous form of the church is seen; and no one is permitted to spurn its authority, flout its warnings, resist its counsels, or make light of its chastisements—much less to desert it and break its unity. For the Lord esteems the communion of his church so highly that he counts as a traitor and apostate from Christianity anyone who arrogantly leaves any Christian society, provided it cherishes the true ministry of Word and sacraments. He so esteems the authority of the church that when it is violated he believes his own diminished.
It is of no small importance that it is called “the pillar and ground of the truth” and “the house of God” [1 Timothy 3:15, KJV]. By these words Paul means that the church is the faithful keeper of God’s truth in order that it may not perish in the world. For by its ministry and labor God willed to have the preaching of his Word kept pure and to show himself the Father of a family, while he feeds us with spiritual food and provides everything that makes for our salvation. It is also no common praise to say that Christ has chosen and set apart the church as his bride, “without spot or wrinkle” [Ephesians 5:27], “his body and... fullness” [Ephesians 1:23]. From this it follows that separation from the church is the denial of God and Christ. Hence, we must even more avoid so wicked a separation. For when with all our might we are attempting the overthrow of God’s truth, we deserve to have him hurl the whole thunderbolt of his wrath to crush us. Nor can any more atrocious crime be conceived than for us by sacrilegious disloyalty to violate the marriage that the only-begotten Son of God deigned to contract with us. [Cf. Ephesians 5:23-32.] Institutes of the Christian Religion, Vol. 1, ed. John T. McNeill and trans. Ford Lewis Battles, (Philadelphia: The Westminster Press, reprinted 1977), Book IV.1.10, pp. 1024-1025.
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It is of no small importance that it is called “the pillar and ground of the truth” and “the house of God” [1 Timothy 3:15, KJV]. By these words Paul means that the church is the faithful keeper of God’s truth in order that it may not perish in the world. For by its ministry and labor God willed to have the preaching of his Word kept pure and to show himself the Father of a family, while he feeds us with spiritual food and provides everything that makes for our salvation. It is also no common praise to say that Christ has chosen and set apart the church as his bride, “without spot or wrinkle” [Ephesians 5:27], “his body and... fullness” [Ephesians 1:23]. From this it follows that separation from the church is the denial of God and Christ. Hence, we must even more avoid so wicked a separation. For when with all our might we are attempting the overthrow of God’s truth, we deserve to have him hurl the whole thunderbolt of his wrath to crush us. Nor can any more atrocious crime be conceived than for us by sacrilegious disloyalty to violate the marriage that the only-begotten Son of God deigned to contract with us. [Cf. Ephesians 5:23-32.] Institutes of the Christian Religion, Vol. 1, ed. John T. McNeill and trans. Ford Lewis Battles, (Philadelphia: The Westminster Press, reprinted 1977), Book IV.1.10, pp. 1024-1025.
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