For someone who appears to have so much respect for unborn babies you worship a incredibly immoral god!
From Rex's point of view, that's not possible. His morals come from his god, and everything his god does or orders is, by definition, moral. Everything his god condemns is, by the same definition, immoral. And of course, anything in the bible, by definition comes from his god and is therefore moral.
Perhaps the only thing more pathetic than Rex's primitive approach to morality is his vilification of those who uses the same spurious method to obtain moral guidance, but for geographical or cultural reasons, slavishly obey a different ancient text.