If you read through, you’ll find that none of the named ‘brothers’ were sons of Mary.
If you read the story of Abraham in the book of Genesis, you will hear Abraham refer to his nephew Lot as his brother. Yet he is his nephew.
The earliest extent gospels were likely written in 1st century Aramaic. That language then had a much more fluid understanding of terms like brother, sister, kinsman, etc. Often a person would be called a brother or a kinsman and not be even remotely related, but there would be a kinship ‘bond’.
Now here is the kicker for you. In Scripture we have the following passage: Acts 1: [12] Then they returned to Jerusalem from the mount that is called Olivet, which is nigh Jerusalem, within a sabbath day’s journey. [13] And when they were come in, they went up into an upper room, where abode Peter and John, James and Andrew, Philip and Thomas, Bartholomew and Matthew, James of Alpheus, and Simon Zelotes, and Jude the brother of James. [14] All these were persevering with one mind in prayer with the women, and Mary the mother of Jesus, and with his brethren. [15] In those days Peter rising up in the midst of the brethren, said: (now the number of persons together was about an hundred and twenty
Are all these 120 people brothers of Jesus? But Scripture
says, Mary the mother of Jesus, ‘and his brethren’. Note that it doesn’t say, “Mary, mother of Jesus and his 120 brothers”; it says, "Mary the Mother of Jesus. . .then there is a ‘break, "and his brethren.’ 120 of them more or less.
Scripture also notes in Luke that when Jesus was lost in the temple at age 12, Mary and Joseph returned to search for Him. Alone. Not “Mary, Joseph, and Jesus’ brothers and sisters returned to search for Him”.
And Scripture records that Jesus began His ministry at about age 30. From that point there is no mention of Joseph, who had presumably died.
So Mary would have had to get pregnant starting when Jesus was 12, finishing when He was thirty, and give birth to 120 brothers (and obviously a few ‘sisters’ as they were mentioned) in a total of 18 years.
The oldest of Jesus’ ‘brethren’ by this ‘logic’ would have been 21 at BEST, and some of his brethren as young as 2, assuming a posthumous birth 9 months after Joseph’s death. . .
Still with a bar mitzvah at 13, there would have been a crowd of 13 to 21 year old men by this passage. And attending with the apostles, so a ‘part’ of those who followed Jesus.
So why did Jesus assign His (and presumably ‘their’) mother to ST. JOHN who was not related?
Out of fear that his brothers would be killed? Um, wasn’t St. John, who was older and had been more involved in ministry, an even BIGGER target?
The whole ‘brothers and sisters of Jesus’ simply does not make sense. The idea that He had uterine siblings was never even considered in Christian teaching until around 500 years ago when some arrogant soul read ‘brothers’ and assumed it meant ‘uterine’ and tried to yank and twist Christianity to reflect that teaching.
