Marvel wikia retcons its first appearance as xmen#101, but phoenix force isn’t in this issue, phoenix is. At some point between its publication and now the story must’ve changed to involve a cosmic god, but I wonder if before then phoenix’s origin was intended to be an extreme version of fantastic 4’s origin beyond just an homage.

I just started reading xmen#125 and once again in a flashback this is how the event is described:

Her body was consumed by the intense radiation. But her mind refused to die. Driven by her love for Scott Summers, she achieved her full potential as a psi --becoming, briefly, an entity of pure thought-- before finally reforming as Phoenix.

So when does phenix force actually bocme a thing? Were there any other out of universe (as I’ll reach the in universe ones eventually) explanations of the phoenix’s power before then? Shouldn’t the wiki at least mention if a part of an article is a retcon?

Edit: I think it appears first in xmen 153, where Kitty pryde tells colossus’s sister a bedtime story loosely based on the xmen. In the story Jean’s soul manages to defeat Phoenix.