John Calvin Commentary Deuteronomy 12:32

"What thing soever I command you, that shall ye observe to do: thou shalt not add thereto, nor diminish from it." — Deuteronomy 12:32 (ASV)

Whatever I command. In this brief clause, he teaches that no other service of God is lawful except that of which He has testified His approval in His word, and that obedience is, as it were, the mother of piety. It is as if he had said that all modes of devotion not directed by this rule are absurd and infected with superstition.

From this we gather that, in order to keep the First Commandment, knowledge of the true God is required—knowledge derived from His word and mixed with faith.

By forbidding the addition or diminishing of anything, he plainly condemns as illegitimate whatever people invent of their own imagination. From this it follows that those who, in worshipping God, are guided by any rule except for that which He Himself has prescribed, make false gods for themselves. Therefore, horrible vengeance is denounced by Him against those who are guilty of this rashness, through Isaiah:

Forasmuch as this people draw near me, etc., by the precept of men; therefore, behold I will proceed to do a marvellous work and a wonder: for the wisdom of their wise men shall perish, etc. (Isaiah 29:13–14).

Now, since all the ceremonies of the Papal worship are a mass of superstitions, it is no wonder that all her chief rulers and ministers should be blinded with that stupidity with which God has threatened them.³⁰⁷

³⁰⁷ Addition in French, “avoit menace les anciens Sacrificateurs.”