Musannaf Ibn Abi Shaybah 27915 — What is disliked of a man peering

Al-Huzayl bin Shurahbil said that Sayyiduna Sa'd (may Allah be pleased with him) put his head in and sought permission from the Prophet (peace and blessings be upon him). At that the Prophet (peace and blessings be upon him) said: "Seeking permission has been prescribed only because of the sight."