Why was Jesus called the Son of David?

And when He had come into Jerusalem, all the city was moved, saying, “Who is this?”
So the multitudes said, “This is Jesus, the prophet from Nazareth of Galilee.”

Matthew spent several years with Jesus, and every page of Matthew’s Gospel is steeped in this theme of promise and fulfilment. The genealogy introduces Jesus as the (son of Abraham) and the (son of David) meaning he is in the lineage of two of the most significant people in Bible events. Lineage means the line of family descent.

Matthew studied and learnt from Jesus recording events to prove He was the Messiah. These names are significant in prophesying that Jesus fulfilled concerning Old Testament prophecies. The Jews were waiting eagerly for these things to be fulfilled and the coming Messiah. Matthew witnessed and recorded these events:

2 Samuel 7:12-13
“When your days are fulfilled and you rest with your fathers, I will set up your (seed) after you, who will come from your body, and I will establish his kingdom. He shall build a house for My name, and I will establish the throne of his kingdom forever.”

Samuel is referring to a promise God established with David. Samuel was a contemporary of King Saul and King David. His parents Elkanah and Hannah dedicated him to the Lord, giving the child to the priest Eli to be raised in the temple. In Acts 3:20 Samuel is portrayed as the last of the judges and the first of the prophets. This is a messianic promise of the Messiah coming through the lineage of David. Readers would now by reading the scriptures that He indeed fulfilled the prophecy of the promise:

Psalm 89:3-4
“I have made a covenant with My chosen, I have sworn to My servant David: Your seed I will establish forever, And build up your throne to all generations.”

This Psalm is pointing back at 2 Samuel and reinforces the message. God promised David that his offspring would establish a throne and a kingdom that would last forever ruling from Jerusalem and Israel:

Isaiah 9:6-7
For unto us a Child is born, Unto us a Son is given; And the government will be upon His shoulder. And His name will be called Wonderful, Counselor, Mighty God, Everlasting Father, Prince of Peace. Of the increase of His (government) and peace There will be no end, Upon the throne of David and over His kingdom, To order it and establish it with judgment and justice From that time forward, even forever. The zeal of the Lord of hosts will perform this.”

God’s government would be established on His shoulders as the anointed King, Jesus fulfilled the prophecies as the Son of David. The word counsellor in ancient Israel was portrayed as a wise king. This promise a man would come to sit on the throne of David releasing peace and righteousness. This is also a mirror to what will come when Jesus will establish a new kingdom here on earth from Jerusalem, and once again sit on the throne of David eternally.

All lawlessness, death, corruption, evil, suffering and immorality will be abolished at Mt Zion. The Son of David does not have to be a biological descendent like the Jews think in this case.

The kingship is father to son, but this objection from the Jews falls down as He is greater than David with divine nature according to scripture.