If God is a Spirit then how would God give unto us his Son? Isa tells us, "unto us a child is born..." The child that was born would be the way in which the Son would be given.
Isa 9:6 For unto us a child is born, unto us a son is given: and the government shall be upon his shoulder: and his name shall be called Wonderful, Counsellor, The mighty God, The everlasting Father, The Prince of Peace.
Jesus fully understood this as he said in the book of Hebrews....
Heb 10:4 For it is not possible that the blood of bulls and of goats should take away sins.
Heb 10:5 Wherefore when he cometh into the world, he saith, Sacrifice and offering thou wouldest not, but a body hast thou prepared me:
The body that was prepared for the giving of God's Son was the "child that was born"
Rom 1:3 Concerning his Son Jesus Christ our Lord, which was made of the seed of David according to the flesh;
Going all the way back to Abraham in which God promised his "seed" would be more numerous than the stars, or on the sand sea.
Exo 32:13 Remember Abraham, Isaac, and Israel, thy servants, to whom thou swarest by thine own self, and saidst unto them, I will multiply your seed as the stars of heaven, and all this land that I have spoken of will I give unto your seed, and they shall inherit it for ever.
Who is the seed of Abraham that would be more numerous than the stars in the sky?
Gal 3:27 For as many of you as have been baptized into Christ have put on Christ.
Gal 3:28 There is neither Jew nor Greek, there is neither bond nor free, there is neither male nor female: for ye are all one in Christ Jesus.
Gal 3:29 And if ye be Christ's, then are ye Abraham's seed, and heirs according to the promise.
Jesus's body (the child that was born) was the "temple" in which the Son of God lived.
My body will one day die, but I (the spiritual man) inside will never die.
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