A subtle clue that "brother of Lord" was interpreted as mere Christian brother by Mark, too

[Giuseppe]

Mark 6:3 :

He went away from there and came to his hometown, and his disciples followed him.
...
Is not this the carpenter, the son of Mary and brother of James and Joses and Judas and Simon? And are not his sisters here with us?” And they took offense at him

It is not a coincidence the fact that the mentioned brothers of Jesus are named just there, in Nazaret.

They were Nazarenes.

Weren't they? Hence even there "Mark" (author) is saying us (not even so implicitly) that the real brothers of Jesus were the mere Christians.

[Martin Klatt]

. . .

[Giuseppe]

I am sorry Giuseppe, but now you are going a little overboard. The clue that he is called the son of Mary then followed by named brothers and unnamed sisters isn't subtle but instead straightforwardly pointing at very outspoken blood relations and there is no Nazareth at all mentioned here but his πατρίδα, which begs the question who his father might be, and perhaps that is the real intended message here: nobody knows his father or the truth is to embarrassing to say out loud that Jesus is a bastard and his mother a woman of loose morals having lots of children without any known legitimate father.
If then such a person claims to be a holy man bringing important teachings there is enough reason for the good villagers to take offence at his pretensions just because they know of his real shady provenance. Heck the damning implication is even they probably grew up with him and would know more about his abilities, character and moral worth as well.

The "bastard" is also the demiurge ("carpenter?") as abortion of the divine Sophia ("Mary"?). The demiurge himself, according to the Gnostic myth, didn't know who created him - he was without father - hence the his presumption of being the Unique God.

I don't share the your certainty about what you would call "straightforward reading".

The irony may be that the people of Nazareth reject Jesus in virtue of the same reasons the Gnostics reject the Creator.

[Martin Klatt]

. . .

[Giuseppe]

Ok, but the my point is that if the heaven is (will be) the new homeland of the Christians (so Paul, if I remember well), then there is some irony in the fact that the brothers and sisters of Jesus are named just there, in Nazareth, when the early Christians were called Nazarenes.