Why does the Lord say that if he has not established his covenant with day and night and the order of heaven and earth, then he will not choose an offspring of David to rule over the offspring of Abraham, Isaac, and Jacob?

As the Book of Consolation comes to a close, the Lord gives one final, sweeping assurance that judgment and exile will not be the final word in Israel’s story, or the world’s story. As he did in Jeremiah 33:20–21, the Lord points to his commitment to his world as its creator. He refers again to the covenant he has established with day and night and the fixed order of heaven and earth. This final phrase is a sweeping reference to all the principles and laws that govern how the physical universe functions. The Lord spoke them all into existence and continues to sustain them moment by moment¹. In the same way, he will not abandon his covenant with Israel that reaches all the way back to Abraham, Isaac, and Jacob, and is itself in response to the sin that threatened the Lord’s purposes for Creation. Sin and judgment will not have the final say in the destiny of the world the Lord made and it will therefore not have the final say in the nation through whom he promised to bless the world (Genesis 12:1–3). Jeremiah 33:1–26 has focused on the central role that David’s descendant, the righteous Branch, will play in the Lord’s salvation of his people and he repeats his commitment to raising up this Messiah. He will not reject the offspring of Jacob, that is the people of Israel, because he will not reject his promise to David my servant and will choose one of his offspring to rule over the offspring of Abraham, Isaac and Jacob, the nation with whom he made his covenant. The nations, and the people of Judah themselves, may believe that the Lord has rejected Israel, but he will restore their fortunes and he will have mercy on them.