Is the constriction of the chest after a sin one of the causes for the expiation of the sin?

Question:
May Allah reward you, Honorable Shaykh. This questioner says: Is the constriction of the chest that occurs after committing a sin one of the causes for the expiation of the sin?

Answer:
The constriction of the chest is not sufficient; repentance is necessary. Repentance is necessary; the constriction of the chest is not sufficient. So, the fact that he repents and his chest constricts is evidence of his regret, and regret for what has passed is one of the conditions of repentance. Thus, the constriction of the chest after repentance is evidence of regret for what has passed.