The miracle performed on the sick must meet three conditions to be genuine, the illness must be incurable, the cure must be instantaneous, and the cure must be complete. (BULLOCKS)..
Anyhow, If you think that this film is demonising the mother of Jesus, Mary, then you haven't watched the film at all even if you think you did. The film is about a demon who is impersonating the holy Mary and deceiving the people. It was a good underrated film. Could have been made better.