“Various signs and miracles and prophecies oftentimes take place by those who are unworthy, according to some need or condescension, as with Barlaam and the ventriloquism. And elsewhere the Apostles, when they found a certain unbeliever ‘casting out demons in the name of Christ’ and they prevented him and reported him to Christ, Christ told them: ‘Do not stop him, for the one who is not against you is for you’ (Lk. 9:50).”
(St. Anastasios of Sinai, question 20)

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