"In every person who lives unrepentant in sin, there lives a demon, as if in a house, who takes charge over everything within him. When by the grace of God such a sinner comes to contrition over his sins, repents, and ceases to sin - the demon is cast out from him. At first the demon does not disturb the one who has repented because, in the beginning, there is much fervor within him which burns demons like fire and repulses them like an arrow. But then, when fervor begins to grow cold, the demon approaches from afar with its suggestions, throws in memories about former pleasures, and calls the person to them. If the penitent does not take care, his sympathy will soon pass to a desire for sin. If he does not come to his senses and return to his former state of soberness, a fall is not far off. The inclination for sin and the decision to commit it are born from desire - the inner sin is ready, and the outward sin is only waiting for a convenient occasion. When an occasion presents itself, the sin will be accomplished. Then the demon will enter again and begin to drive a person from sin to sin even faster than before. The Lord illustrated this with the story about the return of the demon into the clean, swept house."
(St. Theophan the Recluse)
