Are sexual thoughts a mortal sin?

I was wondering if having sexual thoughts would be considered a mortal sin? What about in the case of a married man having sexual thoughts about his wife?


Thoughts about sex are not sinful in themselves. But if they cause desire, they are temptations. To deliberately encourage them, is mortally sinful. Such thoughts about one’s spouse are not ordinarily temptations.

Fr. Vincent Serpa, O.P.

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