Jesus wasn't the seed of David either, from his loins.

"I have made a covenant with my chosen, I have sworn unto David my servant, your seed will I establish forever, and build up your throne to all generations."

Psalm 89:3–4


Jeremiah 23:5-6 "Behold, the days are coming," says the LORD, "That I will raise to David a Branch of righteousness; a King shall reign and prosper, and execute judgment and righteousness in the earth. In His days Judah will be saved, and Israel will dwell safely; now this is His name by which He will be called: THE LORD OUR RIGHTEOUSNESS.

In Jesus times, Judah wasn't saved. They were under Roman control.