The Messenger of Allah ﷺ said, "You have a reward in being intimate with your wife."Someone asked, "Messenger of Allah, can there be a reward in fulfilling desire?"He replied, "Yes. Tell me, if you had a son who reached maturity and then died, would you hope for reward from Allah for him?"The man said, "Yes."The Prophet asked, "Was it you who created him?"He answered, "Rather, Allah created him."The Prophet asked, "Was it you who guided him?"He answered, "Rather, Allah guided him."The Prophet asked, "Were you the one who provided his sustenance?"He answered, "Rather, Allah was the one who sustained him."The Messenger of Allah ﷺ said, "So place it in what is lawful for you and keep it away from what is unlawful, and entrust the matter to Allah. If He wills, He will give it life, and if He wills, He will cause it to die, and you will have a reward."
أن رسول الله ﷺ قال: لك في جماع زوجتك أجر فقيل: يا رسول الله وفي شهوة يكون من أجر؟ قال: نعم أرأيت لو كان لك ولد قد أدرك، ثم مات أكنت محتسبه؟ قال: نعم، قال أنت كنت خلقته؟ قال: بل الله خلقه. قال: أنت كنت هديته؟ قال: بل لله هداه، قال: أكنت ترزقه؟ قال: بل الله كان رزقه، قال رسول الله ﷺ: فضعه في حلاله وجنبه حرامه، وأقرره، فإن شاء الله أحياه، وإن شاء أماته، ولك أجر.
Ibn Hibban narrated it (4192), from Ibn Salm, who said, Harmalah told us, who said, Ibn Wahb told us, who said, Amr bin Harith informed me, that Saeed bin Abu Hilal told him, from Abu Saeed the freedman of Mahri, from Abu Dharr, and he mentioned it. Its chain of transmission is hasan because of Abu Saeed the freedman of Mahri, for Ajli deemed him trustworthy, as did Ibn Hibban, and Muslim included a report from him in his Sahih. Fasawi mentioned him among the trustworthy successors from the people of Egypt, and a group of narrators reported from him, so he does not fall below the rank of one whose hadith is hasan. Abu Salam corroborated him in some of what he narrated, as will be seen in the following hadith.