There's been some confusion regarding religion and the Atom, so to set my own head straight, I figured now would be a good time to explore the matter.
I don't believe the faith (or lack thereof) of Al Pratt has ever been dwelt upon. The name Pratt is Dutch, and the Netherlands were good for Jews until the Nazi occupation, but nothing in his personality strongly indicates a specific religious background.
Ray Palmer's mother was Jewish, which makes Ray one by birth. "Half-Jewish" is kind of a wonky term, because according to Jewish law, you either are or are not one. You can lay secular claim to being half-Jewish through your father, but since it's passed through the mother, Talmud would designate Ray as fully Jewish. Obviously, stated/practiced faith and communal acceptance would come into play. However, Susan Palmer was almost certainly non-practicing, as her adult son claimed ignorance of the Hanukkah story. Ray married Jean Loring in a church (not that she wouldn't have insisted,) and has expressed atheistic sentiment (unceasingly favoring science over the supernatural.) Despite my own occasional claims and others I've heard (including my recent accidental and stomach-turning visits to two white supremacist message boards,) Ray Palmer is likely only Jewish by the broadest standard.
Albert Rothstein is pretty unambiguously Jewish. For starters, his name is Albert Rothstein. Al has popped up in a Hanukkah-centric story or two, and turned down a relationship with Beatriz (Fire) da Costa because she wasn't of the faith (also: trampy.)
I don't recall Grant Emerson ever being remotely religious.
I'm open to correction here, but I thought I remembered Ryan Choi being an atheist.
So okay, we've established that despite popular misconception, none of the Atoms are especially Jewish, but Atom-Smasher is. I'm kind of bummed about that, but there you go.
