Religious beliefs, even irrational ones, are not in themselves a sign of mental illness, though many are a sign of gullibility.
But a religious/superstitious person who hears voices is less likely to seek diagnosis of a mental illness if their religion allows/encourages them to believe they're the voices of god/angels/spirits etc.
But a religious/superstitious person who hears voices is less likely to seek diagnosis of a mental illness if their religion allows/encourages them to believe they're the voices of god/angels/spirits etc.