٤٥٠١ - حدثنا ابن علية عن ابن عون قال: سألت محمدا عن شيء من الوهم في التطوع، فقال: لا أدري أين موضعه؟ فقلت: أسجد بعده سجدتين قال: أتشبهها بالمكتوبة أما أنا فلو كنت لم أفعل.
Ibn Aun says that I asked Muhammad whether doubt (uncertainty) is considered in voluntary (nafl) prayers. He replied, "I do not know what its status is." I asked, "In the case of doubt in nafl, should two prostrations of forgetfulness (sajda sahw) be performed?" He replied, "Do you consider nafl to be similar to obligatory (fard) prayers? If such a situation happened to me, I would not perform sajda sahw."