This is not some post about whether Jesus and Mary Magdalene had a child it is a post about the siblings of Jesus.
The Bible says that Jesus had brothers and sisters:
"Is not this the carpenter's son? is not his mother called Mary? and his brethren, James, and Joses, and Simon, and Judas? And his sisters, are they not all with us? Whence then hath this man all these things?" (KJV, Matthew 13:55-56)
It is the only chapter which specifically names the brothers of Jesus and mentions he has sisters. There are other verses which refer to them though; these are Matthew 12:46, Luke 8:19, and Mark 3:31.
So where did they come from?
Nobody knows. There are 3 main views:
- The siblings are of Mary and Joseph after the birth of Jesus.
- The siblings are from a previous marriage of Joseph.
- The siblings were in fact cousins of Jesus.
Are they the children of Joseph and Mary born after Jesus' birth? Unlikely. The birth of Jesus is the miracle virgin birth; so if Mary gave birth after that it would be mentioned. If you can mention a wedding that Jesus attends then it stands to reason that the birth of Jesus' brother would be mentioned also; along with some parable and such.
Are they from a previous marriage of Joseph? The Bible makes no mention of Joseph being married before Mary. But the apocryphal text 'The Protoevangelium of James' states that Joseph was a widower, an old man, and had sons. The apocryphal text 'The Infancy Gospel Of Thomas' also states that Joseph had at least one son who is called James.
Are they cousins? Thanks to translation the idea that they are cousins works in one way. The Greek word used for 'brother' also denotes more distant relationships unlike its English counterpart. The problem is that early Christian literature refer to then specifically as the 'brothers of the Lord'.
Which one is correct? Your guess is as good as any. All things considered it is likely that the brothers and sisters mentioned were either full or half siblings; with most biblical scholars leaning to the idea of half-siblings.
The chances of a full Holy bloodline is very unlikely but there is definitely a bloodline which should have some sort of special meaning seems it is from the family of Jesus. But to prove it you'd need to be able to find the remains of Joseph, his sons and daughters, and then hope that yo can get a decent DNA sample from all. But even with a DNA sample from all you would then need to be able to reliably trace their descendants and get DNA samples and trace more and more generations.
So is there a holy bloodline? Most likely, even though it is from the half-brothers and half-sisters of Jesus, but proving it is another thing. But, just as a thought the person sitting across from you as you read this could be a descendant of Jesus' family. Might be a good time to say "Hi" and see about them putting a good word in for you.