You are our epistle written in our hearts, known and read by all men; clearly you are an epistle of Christ, ministered by us, written not with ink but by the Spirit of the living God, not on tablets of stone but on tablets of flesh, that is, of the heart (2 Cor. 3:2-3).
In the fourth century, a Syrian monk, now referred to as Pseudo-Macarius (because the writings were wrongly attributed to an Egyptian monk named Macarius), commented that the word of God written in our hearts is more valuable than the Scriptures. The Scriptures remain as ink on a page and are external to us. But the word which God writes on our hearts becomes one with us and inseparable from our daily lives. [See also, The Heart as God’s Hearth]. When the word is written on our hearts it speaks directly to all the organs of the body and helps guide our thoughts, emotions and actions.
“It is like this in Christianity for anyone who tastes the grace of God. For it says: ‘Taste and see how sweet the Lord is” (Ps 34:8). Such a taste is this power of the Spirit working to effect full certainty in faith which operates in the heart. For as many as are sons of light and in the service of the New Covenant through the Holy Spirit have nothing to learn from men. For they are taught by God. His very grace writes in their hearts the laws of the Spirit. They should not put all their trusting hope solely in the Scriptures written in ink. For divine grace writes on the “tables of the heart” (2 Cor. 3:3) the laws of the Spirit and the heavenly mysteries. For the heart directs and governs all the other organs of the body. And when grace pastures the heart, it rules over all the members and the thoughts. For there, in the heart, the mind abides as well as all the thoughts of the soul and all its hopes. This is how grace penetrates throughout all parts of the body” (The Fifty Spiritual Homilies, pp. 115-116).
And the word of God written on our hearts prepares us for our judgment before God on the last day. For when the “books are opened” by God to determine our fate, the book which is our heart will also be open for God to see what is in our heart. Not only will God see what is written on our heart, but all the angels in heaven will also see our heart exposed. No more secrets! All those things we have been hiding from others and hoping no one will ever know about us will be visible to all on the judgment. “For nothing is covered that will not be revealed, or hidden that will not be known” (Matt. 10:26). For example, Origen writing at the beginning of the third century says:
“And I believe that this is what is indicated by Daniel when he says, ‘And the books were opened‘ (Dan 7:10); namely, those that are now rolled up and covered in our heart, containing the writings of what we do. They are etched in a certain alphabet of the conscience, yet are fully known to no one except God alone. So then, these books of our soul or pages of our heart will be opened in the presence of the throne of fire and the wheels of blazing fire and the river of fire that flows before the Ancient of Days. Even the angels will see these things and read them . . . And so, for our crimes in which now we are disconcerted to allow even one witness, then we shall have to endure the innumerable throngs of the heavenly powers as witnesses” (Origen, Commentary on Romans, books 6-10, p 244).
How does one clear one’s heart of these sins? Repentance and confession. By seeking God’s mercy and forgiveness for our specific sins now in this world, we allow God to cleanse our hearts so that on the Judgment Day, there will be no witness written in our hearts to our misdeeds.