"For what the law could not do, in
that it was weak through the flesh,
God sending his own Son in the
likeness of sinful flesh, and for sin,
condemned sin in the flesh:"
Romans 8:3

He got his human nature from Mary.
"Let this mind be in you, which was
also in Christ Jesus: Who, being in the
form of God, thought it not robbery to
be equal with God: But made himself of
no reputation, and took upon him the
form of a servant, and was made in the
likeness of men: And being found in
fashion as a man, he humbled himself,
and became obedient unto death, even
the death of the cross."
Philippians 2:5-8

He existed as God but took on human form.
"...the Word was made flesh, and dwelt
among us..." John 1:14

The divine Spirit clothed Himself with a
human body and the limitation of man.

Simple put the Son of God came into the
world as a person. And became Our Saviour!