Impurity is alienation, and alienation after menstruation is harm, and harm necessitates distance, and I mean special harm, such as his saying, “Those who harm God and His Messenger, may God curse them,” that is, keep them away, and the curse is distance, and its cause is harm from them, so it is far from the Holy Name, and fasting necessitates closeness to God, to whom there is nothing like it. And fasting has no equal in acts of worship. Just as proximity and distance do not coexist, so do fasting, impurity, and harm .