I see nothing blasphemous in it at all, and the opening lines are sheer bloody poetry.

There is a historical inaccuracy though; Joseph died before the crucifixion (this is why he commended Mary to the care of John the Beloved; if Joseph were still alive that would not have been necessary).

But that's neither here nor there. It's a very powerful and commendable song, not the least bit blasphemous, and you are to be congratulated for writing it.

On the "free market" thing -- well yes it is based on older ideas, but nevertheless reading our market-based understanding of the world back into the 1st century AD (or CE) is more than a little anachronistic, IMHO. The idea of the apostles sitting around discussing what symbol to use based on what would sell best is ludicrous.

Alex