2 Corinthians 3:3,”…you are a letter from Christ…written not with ink but with the Spirit of the living God, not on tablets of stone it on tablets of human hearts.”
What does Paul mean here? In the immediate context he’s talking about “letters of recommendation” (that is, letters proving him to be a trustworthy preacher of the gospel). Paul says he doesn’t need such letters because the Corinthians themselves are his letter of recommendation.
In other words, the changed hearts–and therefore changed lives–of the Corinthians are the proof of Paul’s apostleship. This is a much weightier letter of recommendation than any other that Paul could give because this one is not written by means of ink, but by means of the Spirit, and it is not written on stone, but written by Christ Himself on the tablet of the human heart.
With this last phrase (stone vs human hearts), Paul has begun to move into a comparison between the Old Covenant (summarized by the “Ten Commandments” written by the finger of God in tablets of stone on Sinai, Exodus 31:18) and the New Covenant (which will result in the eternal law of God written on the hearts of His people, Jeremiah 31:33, etc)–of which he has been made a minister.
Paul is claiming that to receive his message–the gospel of the glory of God in the person of the crucified and risen Christ (1 Cor. 1:23; 2 Cor. 4:4-6)–is to be gathered in to the New Covenant people of God and so to have the law of YHWH–the law which is LOVE, as revealed and defined on Calvary–written on one’s heart by the Holy Spirit. The same God who etched His Name-revealing law into the stones of Sinai, now reaches–through the declaration of the gospel and by the means of His Holy Spirit–into the hearts of all peoples to etch His law on the foundation and spring of their being…..
And what does this heart-etching look like? What is the content inscribed in the roots of our nature by the Spirit of God? I would content that one faithful answer—one that summarizes all other possible answers in itself—is found in 2 Cor.4:6,…the content etched therein is “the knowledge of the glory of God in the face of Jesus Christ.”….a glory known most definitively on Calvary.