Jer 23:5-6, Jer 33:15, Zech 9:9, Mt 21:4-9

The Old Testament prophesied that God would send Christ, a king from the descendants of David, and that Christ would rule over us. (Isa 32:1-4, Jer 23:5-6, Jer 33:15, Zec 9:9)

Isa 32:1 Behold, a king shall reign in righteousness, and princes shall rule in judgment. 2 And a man shall be as an hiding place from the wind, and a covert from the tempest; as rivers of water in a dry place, as the shadow of a great rock in a weary land. 3 And the eyes of them that see shall not be dim, and the ears of them that hear shall hearken. 4 The heart also of the rash shall understand knowledge, and the tongue of the stammerers shall be ready to speak plainly.

Jer 23:5 Behold, the days come, saith the Lord, that I will raise unto David a righteous Branch, and a King shall reign and prosper, and shall execute judgment and justice in the earth. 6 In his days Judah shall be saved, and Israel shall dwell safely: and this is his name whereby he shall be called, The Lord Our Righteousness.

Jer 33:15 In those days, and at that time, will I cause the Branch of righteousness to grow up unto David; and he shall execute judgment and righteousness in the land.

Zec 9:9 Rejoice greatly, O daughter of Zion; shout, O daughter of Jerusalem: behold, thy King cometh unto thee: he is just, and having salvation; lowly, and riding upon an ass, and upon a colt the foal of an ass.

According to the prophecy of the Old Testament, a king, Christ, has come as a descendant of David. That is Jesus. (Mt 21:4-9)

Mt 21:4 All this was done, that it might be fulfilled which was spoken by the prophet, saying, 5 Tell ye the daughter of Sion, Behold, thy King cometh unto thee, meek, and sitting upon an ass, and a colt the foal of an ass. 6 And the disciples went, and did as Jesus commanded them, 7 And brought the ass, and the colt, and put on them their clothes, and they set him thereon. 8 And a very great multitude spread their garments in the way; others cut down branches from the trees, and strawed them in the way. 9 And the multitudes that went before, and that followed, cried, saying, Hosanna to the son of David: Blessed is he that cometh in the name of the Lord; Hosanna in the highest.