Hadith 17:732
Yahya ibn Ubayd narrated to us, from Abu Hayyan, from Mujammi’, who said: Ali built a prison and named it "Nafi'" (Beneficial). Then, it occurred to him, so he tore it down and built one more secure than it. Then he recited a line of poetry: "Do you not see a clever, sagacious one? I built, after Nafi', a place of confinement (Mukhays)."
حدثنا يحيى بن عبيد عن أبي حيان عن مجمع قال بنى علي سجنا فسماه نافعا ثم بدا له فكسره وبنى أحصن منه ثم قال بيت شعر % ألم تر كيسا مكيسا % بنيت بعد نافع مخيسا %