The world of apostate Christendom had well over a thousand years to interpret the scriptures before the restoration. Some of the plainest parts of the gospel have been spiritualized away into nothing, and probably the most prominent of these is that Jesus Christ is the son of God.
We believe, and we are the only people under heaven that believe, that Jesus Christ was the literal son of a literally living God. Why is it important that God the Father has a body? Because without a body he could not have had a child. Christ was begotten and born as the child of a father and a mother in the usual way that children are begotten and born. His father was Heavenly Father, and his mother was Mary.
The Greeks and Romans had a theology filled with pagan gods having affairs with mortal women. Nobody had any question what was being claimed when it was said that Christ was the Son of God.
In the days of his mortality Christ's sonship was taught openly. When Peter said "Thou are the Christ, the Son of the Living God", Peter could not possibly have been misunderstood.
And it took thousands of years of spiritualizing away at the word "son" to turn something as clear as the fact that the Father had a son by a mortal woman into a mere meaningless nothing in which the Father creating Christ by chemical magic. To do so would make Christ his creation. But it would not make Christ his son. And it is offensive to reduce the Son of God to a chemisters magic trick instead of to the literal son of the living God.
Christ has an eternal family. His father and mother in eternity will be Heavenly Father and Mary. Naturally, Mary was sealed to the Father in accordance with the Father's own divine law.
Mary was both pure and was not given to any mortal man. The authors of the scriptures choose to describe her pure state using the word "virgin", which to our ears is confusing. It differentiates her from the pagan theologies of her day. In the scriptures the word virgin emphasizes that a woman is pure and is not given to any man.
In Shakespeare's play "Much ado about nothing" we see a statement of virtue being made with the words "And surely as I live, I am a maid." To us, that sounds like she is a cleaning lady. But to their ears it was a statement of chastity.
And to ancient ears the word that was translated "virgin" was the best way to convey the fact that she had not been given to any other mortal man and that thereby her marriage to Joseph while carrying the living son of the Father was honorable and right.
But nobody wondered what it meant that God had a son by her.