The other half kind of relies on the Supcom fan series of novels which in my opinion might as well be canon.
It also conveniently provides a better explanation than some wishful thinking on the part of a 14 year old autist who just wants to scream 'deus vult' while playing UEF.
But here's the quote from the nineth book
"Weisman in particular watched with a mixture of awe and disbelief, having finally realized that the Captain’s unusual serenity was partially a matter of faith.
Centuries of warfare against the Aeon Illuminate had slowly created a religious taboo in the military. Personal beliefs were still allowed of course, but few ever spoke of them openly. Only Ferguson appeared completely relaxed as he kept talking: “All that he took in exchange was my hand. I know it is illogical, but it would seem like an insult to ignore his gift, even after so many years.”
Aurium stepped in then, purposely provoking their loyalist guests even as he took a bite from his plate: “Kind of different from The Way, huh?”
“It is,” replied Tamias humbly while putting a hand on Elkins’ arm to silence him: “But we will respect your custom and not mention your wound again.”"