Musnad Ahmad 30:2398

Yahya narrated to us, from Ibn ‘Ajlan, he said: I heard my father narrating from Abu Hurairah, from the Prophet, peace and blessings of Allah be upon him; and Abu al-Zinad, from al-A’raj, from Abu Hurairah, from the Prophet, peace and blessings of Allah be upon him, who said: "If a man were to look into your house without your permission, and you threw a pebble at him and put out his eye, there would be no blame upon you."