The Greek adjective graptos means written or inscribed — derived from grapho (to write). It appears only once in the New Testament (Romans 2:15), describing the law 'written on the hearts' of Gentiles who instinctively do what the law requires. The word points to moral inscription — knowledge of right and wrong etched into human conscience by God.
Paul's use of graptos in Romans 2:15 is theologically significant: it establishes that all humanity, not just Israel, has received God's moral revelation. The law written on the heart is the basis for universal moral accountability. Theologians connect this to natural law, general revelation, and the image of God (imago Dei) in every person. Jeremiah 31:33 promises the New Covenant will also be written on the heart — moving from external law to internal transformation. The same God who writes on stone (Exodus 31:18) writes on hearts (2 Corinthians 3:3).