Who knows what Ar Ar meant? He rarely knows or understands what it is he believes, except to say that he believes what he believes, and what he believes, he believes is right.<quoted text>
He probably meant Judaism. It's pretty unlikely he meant Sumerian mythos, though it's possible, since he uses the word "ancient."
When he argued he wasn't a Protestant over on PTAG:
RiversideRedneck wrote: " If anything, I'm Pentecostal, or maybe even Evangelical, but not Protestant."
When he mentioned "ancient religion", there is no telling what he had in mind. It could have been Judaism, older Canaanite beliefs, or as you said, ancient Sumerian practices.
In retrospect I think he meant Christianity, it's just that his writing and terminology is so vague and misinformed he makes these claims or statements and when someone responds - to what he actually said, not what he thought he said - he gets upset.