God is spirit. And Jesus is only God’s Son in a spiritual sense, not in a physical way.
If someone says, “You are the Son of the Cedars” it means that person is from Lebanon. Or, if from Egypt, “You are the Son of the Nile.” To say that Jesus is the Son of God, means that Jesus is from God. It is like a title. When the angel appeared to Mary, the angel said, “the holy One to be born will be called the Son of God.” A title. Christians do not believe that God had any sexual relationship with any woman.
Isaiah said, “For a child is born to us, a son is given to us. The government will rest on his shoulders. And he will be called: Wonderful Counselor, Mighty God, Everlasting Father, Prince of Peace.” He is God, who became a man, through Mary. He is God and Son at the same time, born of the virgin Mary.
Why do you think God allowed Jesus to be born from a virgin Mary?
To be born of a woman, and not from a man & woman, means he did not take on the sinful nature of Adam and Eve. When Adam and Eve fell into sin, they passed on the sinful nature from one generation to another, through their own children, down to us.
We are all born as sinners. We’re all born with a tendency toward doing things our way, instead of God’s way. We all sin. That’s why the prophet David cried out, “With sin, my mother conceived me.” We all were born with sin. We live as sinful people and we all need a redeemer.
But for Jesus to redeem us, he needed to have a different nature. He needed to be from the spirit of God, the Holy Spirit, no sinfulness at all. Isaiah said, “No deceit was found in him.” No sin in him.
In Scripture, God took on the form of a burning bush when revealing himself to Moses. He took on the voice of heaven when speaking to Abraham. Who is to say that God is not allowed to take on the form of man in order to reveal himself to us?