Adam Smith himself never claimed it was that simple. He also wrote on ethics (and regarded that book as more important IIRC). He also warned that those is the same trade would inevitably conspire against the public.
Quite likely, unfortunately. Having read both The Theory of Moral Sentiments and The Wealth of Nations I think he's insightful and had his head screwed on properly...and disagree with at least 90% of his fans.
I think interpreting this in a modern context, "religious" can be translated as "ethical"