He instructed him to ask the Messenger of Allah ﷺ on his behalf about a man who, when he draws near to his wife, has prostatic fluid come out of him, what is required of him, "for his daughter is married to me, and I feel too shy to ask him myself."Miqdad said, "So I asked the Messenger of Allah ﷺ about that."He replied, "When any of you finds that, let him wash his private part and perform ablution as he does for prayer."
حدثنا عبد الله بن مسلمة عن مالك عن أبي النضر عن سليمان بن يسار عن المقداد بن الأسود أن
أمره أن يسأل له رسول الله ﷺ عن الرجل إذا دنا من أهله فخرج منه المذي ماذا عليه فإن عندي ابنته وأنا أستحيي أن أسأله قال المقداد فسألت رسول الله ﷺ عن ذلك فقال إذا وجد أحدكم ذلك فلينضح فرجه وليتوضأ وضوءه للصلاة
[Sahih] Ibn Majah related it in the Book of Purification, chapter on wudu after emitting madhi, hadith 505, and Nasai, hadith 156, 441, from the hadith of Malik through this chain, and it is found in the Muwatta (Yahya: 1/40). The hadith has corroborating narrations in Muslim, hadith 303, and elsewhere.