Couple more interesting things to help you in your study lewis.
Matt.27
[56] among whom were Mary Mag'dalene, and Mary the mother of James and Joseph, and the mother of the sons of Zeb'edee.
[61] Mary Mag'dalene and the other Mary were there, sitting opposite the sepulchre.
Matt.28
[1] Now after the sabbath, toward the dawn of the first day of the week, Mary Mag'dalene and the other Mary went to see the sepulchre.
Mark.16
[1] And when the sabbath was past, Mary Mag'dalene, and Mary the mother of James, and Salo'me, bought spices, so that they might go and anoint him.
[9] Now when he rose early on the first day of the week, he appeared first to Mary Magdalene, from whom he had cast out seven demons.
Mark.15
[40] There were also women looking on from afar, among whom were Mary Mag'dalene, and Mary the mother of James the younger and of Joses, and Salo'me,
[47] Mary Mag'dalene and Mary the mother of Joses saw where he was laid.
John 19
[25]
So the soldiers did this. But standing by the cross of Jesus were his mother, and his mother's sister, Mary the wife of Clopas, and Mary Mag'dalene.
[26] When Jesus saw his mother, and the disciple whom he loved standing near, he said to his mother, "Woman, behold, your son!"
[27] Then he said to the disciple, "Behold, your mother!" And from that hour the disciple took her to his own home.
[28]
Luke 24
[10] Now it was Mary Mag'dalene and Jo-an'na and Mary the mother of James and the other women with them who told this to the apostles;
Okay, we have this Mary who is the mother of James in Mark 16 and Luke 24. We have "the other mary" and Mary the mother of Joses in Mark 15 and Matt 27, 28 respectively. Mary the mother of Joses and the other Mary are identified as being with Mary Magadalene when they watch where Jesus is laid. Mary the Mother of James is the Mary, with Mary Magadalen when they tell the apostles (luke 24) they have seen the Lord. Mark 15 has Mary Magdalene and Mary the Mother of James the younger (less) looking on from afar. In Mark 15 there is a Mary, looking on from afar who is Mary, mother of James and Joses. Hmmmm.
Seems almost dead certain that "the other Mary", Mary the mother of Joses, and Mary the Mother of James and Joses, and Mary the mother of James the younger (less) are all the same Mary. :-? Note that not once are any of these Mary's identified as Mary the Mother of Jesus and in John 19 it is clear that we have another Mary (Mary wife of Clopas) with the group who is not the mother of Jesus. Further Mary the mother of Jesus is not mentioned in the passages where the women looked on from afar. Probably because she stayed right with the body. Or perhaps seeing her son to distraught it is not surprizing that she might have been taken away by the others. Perhaps John, who's care she was entrusted to and who was not at the tomb with the other two Mary's.
One more point. In John 19 it indicates that John and Mary are near the cross and likely the other women, who are together, are a bit further off. This is consistent with the separation shown in the other two Gospels and again indicates that Mary, mother of James and Joses and Mary the wife of Clopas are the same woman.
I do hope you follow all that. I think your author blew this one bad. As do many other authors who have to prove Mary had other children. Now I am not claiming to prove otherwise, just showing the bias they display in their "exegesis".
Blessings
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