how does a fallen angel become an angel

A fallen angel is usually not described as becoming an angel again in mainstream Christian teaching; the common view is that a fallen angel remains fallen, while redemption is generally framed for humans, not angels. Some theological and fictional traditions, though, do imagine restoration or return to heavenly status.

Mainstream view

In traditional Christian thought, a fallen angel is an angel that rebelled and was cast out, so the “fall” is treated as permanent. The idea is often linked to pride, rebellion, or refusal to obey God.

Redemptive views

A minority of interpretations and speculative writings suggest that fallen beings could be restored through divine mercy or virtue, but that is not the dominant doctrine. One source describes an older theological idea in which beings can return closer to God through virtue, though that view is historically controversial.

In fiction

In stories, the rule is whatever the world-building says it is. Some fiction allows a fallen angel to regain grace, receive forgiveness, or be transformed back into an angel through repentance, sacrifice, or divine intervention.

Simple answer

So, in real-world religious tradition, a fallen angel usually does not become an angel again; in fiction, it can happen if the author writes that kind of redemption arc.

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