Jesus the Son of David
In Luke 1:32, angel Gabriel, announcing to Mary that she will be the mother of Jesus, said about Him that “the Lord God will give him the throne of His father David”. Also in the New Testament we many time see Jesus called son of David. I give below the related references from just the gospel of Matthew:
Returning to what the angel said to Mary – i.e. that God would give Jesus the throne of his father David - his statement means two things: first that Jesus was of David's lineage and second that he had legal rights over David's throne i.e. he was a legal successor of King David. The reality of all these statements is made clear by the two genealogies of Jesus that are given in Matthew 1:1-17 and in Luke 3:23-38. The first of these genealogies refers to the supposed by the society father of Jesus, Joseph, and it shows that he came directly from the regal line of the king David. That’s why, from a legal point of view, Jesus had legal rights over the throne of David. Apart from this legal standing, and since Jesus was not actually a son of Joseph, he also needed to have a physical standing in David's house. This he had through Mary his mother. Indeed, her genealogy that is given in Luke 3:23-38 shows that she was from the house of David. Therefore, both legally and physically, Jesus was of the house of David with direct rights over David's throne.
All these things were not of course accidental. In contrast, they were prerequisites for the Messiah, since according to the Old Testament prophecies the promised Messiah would come from the lineage of Abraham (see Genesis 21:12 and Galatians 3:16) and from the lineage of David (see Psalms 132:11 and Acts 2:29-30). Therefore, since Jesus was the Messiah, he couldn't be but of the lineage of Abraham and David. And he was. Matthew 1:1 expresses this truth very directly:
Therefore the genealogies of Jesus Christ are not a historical enumeration but consist A PROOF THAT JESUS IS THE MESSIAH, THE CHRIST, THE PROMISED ONE, the Son of David and the Son of Abraham. In Him God fulfilled not only His promise to Abraham and to David (Genesis 21:12, Psalm 132:11) but also His promise to the human race (Genesis 3:15) that after the fall waited for the one that would rectify the situation: for the Christ.