Haggai's final message is perhaps the most important. It focuses on the importance of David's descendant in Israel's religious and political life. After the Babylonian exile, the family line of David, in which kings came from the same family, was essential to Israel’s hope of restoration (see Jeremiah 23:5; Ezekiel 37:24).
God had cursed David's descendant, King Jehoiachin, during the exile in Babylon (Jeremiah 22:24–30), but Haggai's last message lifts that curse. It restores the covenant with David (see 2 Samuel 7:4–17) as the way God will fulfill his promises to bless and restore Israel.