The reader: The author (may Allah have mercy on him) quoted
"From Abu Dharr (may Allah be pleased with him) That some people said, "O Messenger of Allah, the people of wealth have taken the rewards. They pray as we pray, they fast as we fast, and they give in charity from the surplus of their wealth." He said, "Has not Allah made available to you what you can give in charity? Indeed, every tasbih is charity, every takbir is charity, every tahmid is charity, every tahlil is charity, enjoining good is charity, forbidding evil is charity, and in the act of intercourse of one of you is charity." They said, "O Messenger of Allah, can one of us fulfill his desire and have a reward for it?" He said, "What do you think, if he placed it in what is forbidden, would he bear a sin? So likewise, if he places it in what is lawful, he has a reward."
أن ناسا قالوا يا رسول الله ذهب أهل الدثور بالأجور يصلون كما نصلي ويصومون كما نصوم ويتصدقون بفضول أموالهم قال أوليس قد جعل الله لكم ما تصدقون به إن بكل تسبيحة صدقة وكل تكبيرة صدقة وكل تحميدة صدقة وكل تهليلة صدقة وأمر بالمعروف صدقة ونهي عن المنكر صدقة وفي بضع أحدكم صدقة قالوا يا رسول الله أيأتي أحدنا شهوته ويكون له فيها أجر قال أرأيتم لو وضعها في حرام أكان عليه وزر فكذلك إذا وضعها في الحلال كان له أجر
Narrated by Muslim"