So, in other words, you have no scripture you can use which clearly teaches this concept. That's interesting. That doesn't do much for your case.
Jesus is the Word of God that came forth out of Gods mouth.
God prepared a body for Him, for when he would come into the world.
A faithful Jewish woman who was a virgin, who was betrothed to a man named Joseph of the House of David, was selected to carry for 9 months according to mans law, then deliver forth the babe.
Between receiving the babe in her womb and delivery, she an Joseph married. The child was thus born coming forth from a human woman’s womb, which is according to the law of nature.
According to Jewish Law and Gentile Law, the child was Legally the son of Mary and Joseph.
According to Jewish Law, ONLY a Jew of the House of David could occupy the Jewish Throne and be King of the Jewish Race.
When God appointed David as a Jewish king, God also established his Throne as an everlasting Throne. Also the city of Jerusalem, the seat of Government of the Jews, and the “kingdom” National Land of Israel, the boundaries of Land God Promised Abraham and his descendants.
Because Jesus, was Lawfully by mans law, a Jew, of the House of David, a son of Joseph...every direct of line of Men...father, grand father, gg, ggg, etc. are all call fathers....and thus Jesus was lawfully the son of each one from Joseph to king David, establishing Jesus’ lawful earthly kingship right.
Because Jesus is also the Word of God, came forth out from God, He is God ...... Satisfying Gods Law that only God Can rule Gods Earthly Kingdom...
For Jesus to be called.....A Jew, a son of Abraham...continue the lineage, of David back to Abraham.
The importance of being connected to Abraham...is the promised land.
Promised to Abraham and his Heirs.
So, what Scripture says, IS Jesus took upon himself the seed of Abraham...which is to say, By being delivered forth from a Jewish woman’s womb married to a man of the House of David...he was lawfully entitled to be King of the Jews AND Sit in King Davids Throne, Rule His Kingdom from Jerusalem and His Kingdom be Abrahams promised land.
And, Every person, who through agreeing to conversion, take in them the Seed of God, Who is Christ, they also take upon themselves the seed of Abraham, and are entitled to be heirs of Abrahams promised land.
Jews are Israel, Gentiles are not Israel, Gentiles do not become Israel, Gentiles do not become Jews......ALL become sons of Abraham, Father of many nations. All become sons of God.
If you have not heard this lesson, and can not find the teaching in scripture, reply with my text. Highlight specific parts.