It is narrated from Sayyiduna Mu'awiyah (may Allah be pleased with him): "The eye is the drawstring of the anus." This hadith is mawquf (a Companion's statement).
(b) Marwan bin Janah transmitted the narration in mawquf form.
Al-Walid bin Muslim said: Marwan is more reliable than Abu Bakr bin Abi Maryam.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 580