If you ask a parent what brings them more joy, their own accomplishments or that accomplishments of their children and grandchildren, almost all will answer the latter.  One of the greatest blessings is the generations.

When David saw that he was living in a place, and the treasured ark of the  covenant was housed in a tent, David wondering about making a temple for a proper place of worship and a resting place for the ark as well.  Through Nathan, the LORD told David that he was not to build it, but one of his sons was to build it.  But he gave David a special promise:

“Your house and your kingdom will endure before Me forever, and your throne will be established forever” (2 Sam 7:16).

That’s quite a stout promise.  That your throne would rule forever.  That’s why it was so important that a son of David be seated upon the throne of Israel.  Messiah had to be a son of David.  Which is why we have the geneology we do in Matthew 1:1 that begins, “A record of the genealogy of Jesus Christ, the son of David.”

When Jesus was born as a descendant of David, and died and rose again, he became the ruler forever.  Unbreakable.  Eternal.  Always ruling in the house and line of David.  Jesus fulfilled that.

Had Jesus simply died there would have been the need for another descendant of David.  But since Jesus was raised to life and never dies, there is no one who can ever take his place.  Other rulers can come and rule Israel on earth, but Jesus’ reign is forever.

As Isaiah says (9:7):

For to us a child is born,
    to us a son is given,
    and the government will be on his shoulders.
And he will be called
    Wonderful Counselor, Mighty God,
    Everlasting Father, Prince of Peace.

Of the greatness of his government and peace
    there will be no end.
He will reign on David’s throne
    and over his kingdom,
establishing and upholding it
    with justice and righteousness
    from that time on and forever.

A promise was fulfilled.  And David, a man after God’s own heart, was highly honored.  It was the greatest blessing the LORD could give David.  And ultimately we are all blessed through it.