Romans 1:3,4

Who, on the human side — as if to show that the prophecies were really fulfilled in Him — was born of the seed of David, the rightful lineage of the Messiah; who, on the divine side, by virtue of the divine attribute of holiness dwelling in His spirit, was declared to be the Son of God, by that mighty demonstration, the resurrection of the dead.

According to the flesh. — The word is here used as equivalent to “in His human nature, in that lower bodily organisation which He shares with us men.”