How Do I Know Whether Clairvoyance is from God?

St. Joseph of Optina

From the life of St. Joseph of Optina.

The Elder [Ambrose], and Father Joseph were asked the same question about how to find a clairvoyant person, "one meets a man, apparently clairvoyant, and yet it feels there is something wrong, how do you know whether his clairvoyance is from God?" Both ascetics said the same: "Recognize these people by humility. Because the enemy can give clairvoyance to a person, but he never gives humility - it burns himself".
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Delusion is a Result of Pride and Self-conceit; Delusion is Reduced Through Menial Jobs

Letters of St. Joseph of Optina

St. Joseph of Optina

Your Mavra, as it can be seen from your description, is in delusion. - What to do? It happened and is happening sometimes here as well. Our deceased elders recommended menial jobs for such deluded persons. As delusion is a result of pride and conceit, the damned pride is reduced, at least to some extent, through menial jobs. You should make Mavra help in your kitchen with anything she can, for example, cleaning potatoes or washing the dishes, and so on. She should not be allowed to lead a solitary life under any circumstances. For, as you have noticed, she will become crazy. She should not take the Holy Communion often as well. Let the confessor first to persuade her to humility and self-abasement.

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Novice Evstolia, a prayerful person, is afraid of falling into delusion. - Let her keep the God-pleasing humility, believing herself in her heart to be the most sinful of all the persons, and then she will not fall into delusion. For, according to the remark of Holy Fathers, "humility cannot fall".
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