resulting in the birth of Jesus, 2nd Adam.
So the plan, word of God and power came down from heaven and produced the 2nd Adam. That is the very context of -> the second man from heaven.
Human woman doesn't get pregnant by themselves, it takes a father also, the combination of a sperm and an egg produces a baby, see I passed my basic biology.
The Father sent the Holy Spirit to Mary, again we see 2 (my biology) the Spirit and Mary. Jesus is born of the two, the Spirit is embedded in the human nature of Mary, with Mary being human it produced the flesh, in the likes of "The word became flesh"
What you are saying is that Jesus had human nature only, no regard for Father.
Look at John the Baptist, he was born of both Zacharia and Elizebeth, the natural way.
Jesus Spirit and Mary, can you spot the difference.
