Hadith 4:239
Ibn Fudayl narrated to us, from Layth, from Abdullah, from Mujahid, from Aisha, who said: The Messenger of Allah (may Allah bless him and grant him peace) would sometimes call for his lunch and not find it, so he would impose fasting upon himself for that day.
حدثنا بن فضيل عن ليث عن عبد الله عن مجاهد عن عائشة قالت ربما دعا رسول الله صلى الله عليه وسلم بغدائه فلا يجده فيفرض عليه الصوم ذلك اليوم