@AimsAndObjectives yes, I think you're right that there are better tenets of Christian belief I could have picked. For me, the most non-sensical one is the idea that Jesus was conceived without sperm.
@Cairngormwildfire yes, I imagine many Christians believe that god started the process of the big bang.
Sunnibee has been posting lots of thoughts on what gender identity means and why it's reasonable to allow medicalisation as a means to support someone whose gender identity doesn't match their sex. There has been a lot of criticism from PPs about not really answering what gender identity is.
I think it's as impossible to argue what gender identity actually is as it would be for someone to make a clear case for Jesus being born without sperm.
Put bluntly, to me, Mary had sex with a man other than Joseph and managed to convince everyone that she hadn't. I think this because I know biology is real and I don't believe that god exists. However, I will never convince Christians that I'm right and they will never convince me that I'm not.
The same is true if someone holds a belief in gender identity. Given Sunnibee does hold one, I can see why it's a conundrum to know whether the cruelty is in giving the PBs or not giving them. To me, that's why we each ended up conceding to the other that there was nowhere else for that particular conversation to go. The most interesting moment for me came when we both agreed the most sensible thing to do was complete the data linkage study before undertaking any trial.
Seethlaw's position is different. Yes, there is a belief of some kind of inner self that is masculine, but the difference is in recognising that this may have come from without, e.g. a maternal influence, rather than it absolutely definitely having come from within.
Just as with variations in Christianity, when tenets of the belief colide with biological facts, each believer has to find their own lines between belief and observable, empirically provable reality.
With gender identity, believers who don't want to concede that it's possible that gender identity may not come from within are left with a choice of doubling-down on using tenets of the belief as the only way to be kind or coopting DSDs to "prove" some form of spectrum of sexes. The latter can be completely torn to shreds scientifically.
With Christianity, we're 2000 years too late to bring in paternity tests and CCTV footage of who Mary was hanging around with around the time when Jesus was conceived. Thankfully Christians stopped demanding everyone follow the tenets of their belief a long time ago and the NHS doesn't deliver healthcare based on any of it being real.
Edited for clarity.