1. Christ is the righteousness of God who will save us. (Jer 33:14-17)
    Mt 1:21, Lk 1:32-33, 1 Cor 1:30

In the Old Testament, God said that He would send Christ as the descendant of David to save the people of Israel. (Jeremiah 33:14-17)

Jeremiah 33:14 Behold, the days come, saith the Lord, that I will perform that good thing which I have promised unto the house of Israel and to the house of Judah.
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.
16 In those days shall Judah be saved, and Jerusalem shall dwell safely: and this is the name wherewith she shall be called, The Lord our righteousness.
17 For thus saith the Lord; David shall never want a man to sit upon the throne of the house of Israel;

Jesus is the Christ who came to save the people of Israel as a descendant of David. (Matthew 1:21, Luke 1:32-33, 1 Corinthians 1:30)

Matthew 1:21 And she shall bring forth a son, and thou shalt call his name Jesus: for he shall save his people from their sins.

Luke 1:32 He shall be great, and shall be called the Son of the Highest: and the Lord God shall give unto him the throne of his father David:
33 And he shall reign over the house of Jacob for ever; and of his kingdom there shall be no end.

1 Corinthians 1:30 But of him are ye in Christ Jesus, who of God is made unto us wisdom, and righteousness, and sanctification, and redemption: