Board Thread:Lore Discussion/@comment-24577193-20140222212506/@comment-17114085-20141211145138

From ESO we discover that they don't really worship any deities. They are connected to the Hist, yes, and do have rituals involving the Hist, but they don't worship them as gods or similar divine deities. Draevan's Blog has a quote from an Argonian NPC in the game that explains it well enough.