Welcome to 1789...

I think the religious aspect of the French Revolution is really underestimated/underplayed by historians. It's actually something that historians tend to ignore generally - it's hard for well-educated Westerners to think themselves into a mindset that genuinely believed in hell fire and eternal damnation. For example, look how Thomas More is portrayed in Robert Bolt's play - as a 20thc liberal dying for a principle, rather than what was more likely to be the case, that he was someone who believed being beheaded was better than having his soul damned for eternity (!).

The atheist campaign in France allowed Royalists to incite rural peasants - more religious than urban people - into what was in effect a 'jihad', a 'holy war' against atheist infidels, i.e., the Jacobins and others of urban Paris. The atheists were attempting a reformation that went even further, and at very high speed, than the other religious reformations elsewhere in Europe, which had taken centuries - and a lot of bloodshed - to achieve. The 'Supreme Being' was an attempt to calm things down and seek a middle course with a state religion. It may look bonkers and very very kitsch from this distance but I think it was an attempt to pour oil on troubled waters.