Why did Jesus give his mother to John?

One of the last or 'Seven Words from the Cross' was the commandment of Jesus to two people standing at its foot:  to his mother and to his Apostle, John:

"Near the cross of Jesus stood his mother, his mother’s sister, Mary the wife of Clopas, and Mary Magdalene. When Jesus saw his mother there, and the disciple whom he loved standing nearby, he said to her, “Woman, here is your son,” and to the disciple, “Here is your mother.” From that time on, this disciple took her into his home. (John 19 v 25-27)"

Buhl Altarpiece of The Crucifixion

In effect, Jesus said to his mother 'Go and live permanently with John'. He commanded John to financially and emotionally take care of her, like he would his own mother, for the rest of her life. John's Gospel says that this arrangement took place. This is a mystery because Mary had other children, four sons and a number of daughters, called the family of Jesus, in scripture, which some Catholics find hard to accept - but it is 'there', in black and white.  His brothers were James, Joseph, Simon and Judas and his sisters were not named. There seems to be a later historic text, mentioning the family of Jesus and land they owned:  his was a family who had a direct line of descent from King David. They could have been of interest to the Romans and, politically, an ongoing threat.

Mary, at the Cross, would have been at least forty five years old. She was at least twelve when she gave birth to Jesus, though she could have been as old as sixteen. Jesus was thirty three, so she may have been nearer fifty. She was a crucial part of the Divine Plan of Redemption and a direct descendant of King David, herself. At the start of the ministry of Jesus, she had wilingly, or half willingly, sided with the younger brothers of Jesus, who, St John's Gospel says 'did not believe in Him'. At one point, she and they went to try to force him to give up His ministry and come home with them to Nazareth, telling people he was 'out of his mind' i.e. mentally ill.  Jesus repudiated them by saying that his real mother and brothers were those who did the will of God. Clearly, at that point, they were not doing it and he treated them as he did Peter, with a "Get-behind-me-Satan" type of statement.

John was a very gracious Apostle. The words 'loving and kind' spring to mind, judging from the text of his wondrous Gospel which is, to my mind, the greatest written text in the world. His Epistles show he was very gracious to the women, starting letters with most unusually warm words, such as 'Beloved Lady' etc. What is less well known is that John was also the first cousin of Jesus, the son of Salome, the sister of Mary. He and his brother, James, another one of the Twelve, were the emotional 'sons of thunder', the loving, inventive and mildly critical nickname for them, coined by Jesus. Therefore, John was directly descended from King David and in the royal line. Salome, his mother was still alive, and with her sister, Mary, at the Cross, along with Mary the wife of Clopas. The sisters must have been clinging together, in traumatised shock and grief.

Jesus was saying to his mother "Go and live with your sister, Salome and her son John, my beloved disciple, for whom I will provide and who will provide for you. In this way, you will know that I am still providing directly for you, through him, as your enduringly faithful eldest son".

If the nuclear family means everything today, it was different in those times. The extended family was just as important and a necessary social support system. Jesus may have been thought to be with Salome and John, i.e. his close extended family, when he went missing on the way from Jerusalem, when he was twelve.

The key question is why did he not give Mary to one of his brothers? He also had an unknown number of almost certainly married sisters, as everyone was married then, excluding him. The reason may be that their level of faith was the issue at that point. Clearly, Mary was very close to her sister, Salome and to John who was the only Apostle, as far as we know, faithful at the Cross, and probably there, officially, as a male blood relative. The Cross was an experience that deeply bonded this family group.

Jesus knew the whole story of his family, past present and future. His brother James who came to faith after the Resurrection, became leader of the Jerusalem Church and was martyred. There is a suggestion (I am unsure where) that he was a trained priest. Maybe Mary actually preferred to be with her sister Salome and John, based on the Lake of Galilee and later elsewhere? They were both faithful Christians with a proven track record of courage, utterly loyal to Jesus and Mary. There is a tradition that John became Bishop of Ephesus, the messianic church that the preaching of Paul helped to build, after Mary died in Judea, which included Jerusalem and Galilee.   There is another strand that claims she went to Epehesus, with John, and died there.  There is a House of The Virgin Mary. The truth is 'no one knows'.

Whatever the case, one can be certain that Jesus ensured that Mary felt completely safe, cared for, fully honoured and respected as the 'highly favoured and blessed' woman she was. St John, after all was the one who really knew who the identity of Jesus in the eternal and divine scheme of things.  He wrote "In the beginning was The Word and the Word was with God...and the Word was God."

The Apostle John lived to a great age and does not seem to have been martyred, but ended up as a very old man, on Patmos, a Roman penal colony near Epehesus, possibly around 80 AD. Mary may have lived a long life too, but she may have been in Heaven by then, having been born around 16 BC. Life was generally much shorter in the ancient world. Most of all of the rest of the Apostles were dead by then, having died violently, relatively young.