NOTES for Jer 31:23-40
Speaking about the people's future and the messianic age, Jeremiah uses the concept of a new covenant between God and His people. The covenant made at Sinai is, of course, not abolished; it remains in force, although the people had long violated the terms of that agreement, repeatedly transgressing the Torah given as its foundation. But now the subject is no longer a Torah carved in stone, but a Torah written in the heart.
This Torah written in the heart will become the foundation of the new messianic covenant. After the Babylonian captivity, these words of the prophet were understood anew, and the concept of the inner Torah arose in postexilic Judaism, followed later by that of the living Torah. The inner Torah was no longer an external legal or moral restraint upon a person, but an inner spiritual and moral imperative. Following it was connected not only, or even primarily, with self-restraint, but with ordering one's inner life and then one's outward life according to its norms. This was ascetic work in the proper sense of the word, when asceticism is understood not as self-mortification but as organizing one's inner world, and afterward one's outward life, around a spiritual axis—the inner Torah. Ideally, it alone was to determine a person's life. Such a person became a living Torah; there was no longer room for sin in his life, and the knowledge of God became his ordinary state, just as Jeremiah had said. Of course, for fallen humanity the living Torah remained an unattainable ideal.
It is not by chance that Jesus speaks of the Torah He came not to abolish but to bring to fullness. The first Christians saw in Christ the only earthly example of a living Torah. They understood becoming like Him as the path of the inner Torah, culminating in the Kingdom when the person following Christ's path becomes a living Torah himself, like his Teacher. Thus, with Christ's coming, the revelation once given to the prophet six centuries before His birth was disclosed. This is not surprising: the meaning of every genuine revelation is fully revealed only in the Kingdom for whose sake it was given.