1. From the seed of David, God raised up Christ, the Savior of Israel. (Jer 30:8-9)
    Ezk 34:23-24, Ezk 37:23-25, Hos 3:5, Lk 1:67-69, Acts 13:22-23

In the Old Testament, God said that He would raise up Christ, the true King, from the seed of David to save us and make Him our shepherd. (Jeremiah 30:8-9, Eze 34:23-24, Eze 37:23-25, Ho 3:5)

Jeremiah 30:8 For it shall come to pass in that day, saith the Lord of hosts, that I will break his yoke from off thy neck, and will burst thy bonds, and strangers shall no more serve themselves of him:
9 But they shall serve the Lord their God, and David their king, whom I will raise up unto them.

Eze 34:23 And I will set up one shepherd over them, and he shall feed them, even my servant David; he shall feed them, and he shall be their shepherd.
24 And I the Lord will be their God, and my servant David a prince among them; I the Lord have spoken it.

Eze 37:23 Neither shall they defile themselves any more with their idols, nor with their detestable things, nor with any of their transgressions: but I will save them out of all their dwellingplaces, wherein they have sinned, and will cleanse them: so shall they be my people, and I will be their God.
24 And David my servant shall be king over them; and they all shall have one shepherd: they shall also walk in my judgments, and observe my statutes, and do them.
25 And they shall dwell in the land that I have given unto Jacob my servant, wherein your fathers have dwelt; and they shall dwell therein, even they, and their children, and their children’s children for ever: and my servant David shall be their prince for ever.

Ho 3:5 Afterward shall the children of Israel return, and seek the Lord their God, and David their king; and shall fear the Lord and his goodness in the latter days.

Zacharias prophesied that Jesus, the descendant of David, would save the people of Israel. (Luke 1:67-69)

Luke 1:67 And his father Zacharias was filled with the Holy Ghost, and prophesied, saying,
68 Blessed be the Lord God of Israel; for he hath visited and redeemed his people,
69 And hath raised up an horn of salvation for us in the house of his servant David;

The descendant of David, whom God spoke of in the Old Testament, the true King who will save us, is Jesus Christ. (Acts 13:22-23)

Acts 13:22 And when he had removed him, he raised up unto them David to be their king; to whom also he gave their testimony, and said, I have found David the son of Jesse, a man after mine own heart, which shall fulfil all my will.
23 Of this man’s seed hath God according to his promise raised unto Israel a Saviour, Jesus: