According to Jeremiah 31:33, this divine law is not only put into our spirit but is also written, inscribed, on our hearts. This corresponds to the New Testament teaching about the divine life spreading from our spirit into our heart and mind.
Jeremiah 31:34 tells us that all the house of Israel will know Jehovah, from the little one to the great one among them. This also applies to us, the New Testament believers, today. What makes us different from others is that we have the inner law of the divine life with its capacity and ability to know God and to know that God is our God and that we are His people. Today, as the new creation, we should conduct ourselves according to the inner instruction of the law of life. Eventually, Israel will be the same as we are now; they also will become a new creation in the divine life and know God according to the capacity of the divine life.
We may compare our reading of the book of Jeremiah to picking fruit from trees in an orchard. In picking fruit we do not care about old branches or dry leaves; we care for the ripe fruit. Likewise, in our study of Jeremiah, we should not gather "branches" and "leaves" but "fruit." Those who pay attention to the branches and leaves and those who appreciate the fruit are both right, but only those who collect the fruit are spiritually benefited. In these messages in the life-study of Jeremiah, my burden is to present not branches and leaves but fruit. I believe that even in this introductory word there are a number of "apples," "peaches," and "pears" for you to enjoy. The portions concerning the fountain of living waters, the righteous Shoot who will reign as a King, the Lord's lovingkindness and compassions and His being our portion, and the new covenant with the law of the divine life surely are marvelous fruit for our enjoyment and enlightenment. Whereas many readers of Jeremiah concentrate on the branches and leaves, I would urge you to concentrate on the fruit.
Finally, in this introductory word we need to see that the book of Jeremiah has four sections. The first section is Jeremiah's call and commission (ch. 1). The second section covers Israel's sin against Jehovah and Jehovah's punishment upon Israel (chs. 2—45). The third section concerns Jehovah's punishment and judgment upon the nations involved with God's elect, Israel (chs. 46—51). The last section is a supplement to the history of captivity (ch. 52).
As we have indicated, in these four sections there are four parties: God, Jeremiah, Israel, and the nations. The first two parties are good, and the second two are evil. In a very real sense, the book of Jeremiah is a drama in which an important part is played by each of these four parties.