John Calvin Commentary Philippians 4:7

"And the peace of God, which passeth all understanding, shall guard your hearts and your thoughts in Christ Jesus." — Philippians 4:7 (ASV)

And the peace of God Some, by turning the future tense into the optative mood, convert this statement into a prayer, but this is without proper foundation. For it is a promise in which he points out the advantage of firm confidence in God and of invoking Him.

“If you do that,” he says, “the peace of God will keep your minds and hearts.”

Scripture is accustomed to divide the soul of man, concerning its frailties, into two parts — the mind and the heart. The mind means the understanding, while the heart denotes all the disposition or inclinations. These two terms, therefore, include the entire soul, in this sense: “The peace of God will guard you, so as to prevent you from turning back from God in wicked thoughts or desires.”

He rightly calls it the peace of God, since it does not depend on the present aspect of things, and does not bend itself to the various shifts of the world, but is founded on the firm and unchangeable word of God.

He also rightly speaks of it as surpassing all understanding or perception. For nothing is more foreign to the human mind than, in the depth of despair, nevertheless to exercise a feeling of hope; in the depth of poverty, to see opulence; and in the depth of weakness, to keep from giving way. And, finally, to promise ourselves that we will lack nothing when we are left destitute of all things.

And all this rests in the grace of God alone, which is not known in any other way than through the word and the inward earnest of the Spirit.