'Descendant' in the Bible

The record of the genealogy of Jesus the Messiah, the son (descendant) of David, the son (descendant) of Abraham:

But after he had considered this, an angel of the Lord appeared to him in a dream, saying, “Joseph, descendant of David, do not be afraid to take Mary as your wife, for the Child who has been conceived in her is of the Holy Spirit.

In the days of Herod [the Great], king of Judea, there was a certain priest whose name was Zacharias, of the division of Abijah. His wife was a descendant of Aaron [the first high priest of Israel], and her name was Elizabeth.

to a virgin betrothed to a man whose name was Joseph, a descendant of the house of David; and the virgin’s name was Mary.

Jesus saw Nathanael coming toward Him, and said of him, “Here is an Israelite indeed [a true descendant of Jacob], in whom there is no guile nor deceit nor duplicity!”

However, it is not as though God’s word has failed [coming to nothing]. For not all who are descended from Israel (Jacob) are [the true] Israel;

I say then, has God rejected and disowned His people? Certainly not! For I too am an Israelite, a descendant of Abraham, of the tribe of Benjamin.

Now the promises [in the covenants] were decreed to Abraham and to his seed. God does not say, “And to seeds (descendants, heirs),” as if [referring] to many [persons], but as to one, “And to your Seed,” who is [none other than] Christ.

Why, then, the Law [what was its purpose]? It was added [after the promise to Abraham, to reveal to people their guilt] because of transgressions [that is, to make people conscious of the sinfulness of sin], and [the Law] was ordained through angels and delivered to Israel by the hand of a mediator [Moses, the mediator between God and Israel, to be in effect] until the Seed would come to whom the promise had been made.