This gate shall be opened to no man, for the Lord only will go in by that gate, and again go out, and it shall be shut forever (Ezekiel 44;2).
It is a consistent understanding by all of the Great Theologians of Christendom before 1517 that Christ entered into the womb of the Virgin Mary by the power of the Holy Spirit and and was born (go out) and took his Human Nature from her. After the Incarnation of Christ, it (Mary’s womb) was shut forever.
And again, those brothers of Jesus were never understood to be Mary’s children. James the so called brother of the Lord is actually the Son of another Mary. None of those “brothers of the Lord” are ever called Mary’s child, Christ is several times (John 2:1, Acts 1:14). THe Mark 6:3 you cite, James and Joseph (Joses) were called brothers of the Lord and their Mothers name was Mary. In MT 27:56, we see there were many woman, Mary Magdalene and Mary the Mother of James and Joseph, and the mother of the sons of Zebedee. Is this Mother of James and Joseph Mary the Mother of Christ? I don’t think so.
Look at several other Crucifixion and Resurrection accounts. In MT 28:1 we see “After the sabbath, as the first day of the week was dawning... Mary Magdalene, JOanna and the other Mary (why not Mary the Mother of CHrist). In Luke 24:10 we see another more detailed account and find Mary Magadelene again names, Joanna and Mart the Mother of James (again, not Mother of Christ.
Mark 15:40-47 we see the text indicating that there were also woman looking from the distance, among them were Mary Magadelene, Mary the Mother the younger James, Joses and Salome. Mark 16:1-2 we see Mary Magadelne and Mary the Mother of James and Salome bringing spices.
In reading these texts, the Children are used to identify which “MARY” is being referred to. There 2 being referred to here, Mary Magdalene and the other Mary, The Mother of James, Joses and Salome and this Mary ain’t the mother of Jesus.
John’s Gospel indicates Mary the Mother of Christ was present at the Crucifixion and Jesus committed his Mother to John (why not James, Joses and Salome, if they were Mary, the Mother of Jesus children as well).
John’s Gospel tells us in Verse 25 “Near the Cross of Jesus stood HIS mother and his mother’s sister, Mary the wife of Clopas and Mary Magdala.
Now we now have 2 other Mary’s identified along side Mary the Mother of Christ and as Matthew, Mark and Luke all tell us, this “other Mary” is the Mother of James, Joses, and Salome. Since all 4 Gospels are consistent with there being THREE Mary’s, 1)Christ Mother, 2)Mary Magadelene and 3)The Other Mary, the Mother of James, Joses and Salome, this other Mary seems to be Mary (Christ’s Mother’s) sister, who was the wife of Clopas. Again, look at the text of John 19:25 and I am assuming there are only 3 Mary’s there and Mary’s sisterhood is connected to Mary either by virtue of her being the wife of Clopas (Joseph’s brother) or maybe she was a close relative to Mary the Mother of Christ and called “sister” as the bible used the term brother and sister to describe close relatives including uncles and cousins.
Regardless, James, Joses and Salome are indeed relatives of Christ, but not brothers and sisters of Christ in the sense they were the Virgin Mary’s children.
The Bible does not support it nor does any orthodox theologian of the early Church.
To borrow from the 1970’s song from the rock band queen, another protestant heresy bites the dust.