صحیح ابن حبان
Ibn Hibban
كتاب الصوم
Book of Fasting
باب صوم التطوع - ذكر الإباحة للمرء أن ينشئ الصوم التطوع بالنهار وإن لم يكن تقدم العزم له من الليل منه
Chapter on Voluntary Fasting - Permitting voluntary fasting to be initiated during the day without prior intention at night
1 hadith
Hadith 3628
Mother of the Believers, Lady Aisha Siddiqa (may Allah be pleased with her) narrates: Once the Prophet Muhammad (peace and blessings be upon him) came to me and asked: "Do you have anything to eat?" I replied: "No." The Prophet (peace and blessings be upon him) said: "Then I will fast." Lady Aisha (may Allah be pleased with her) narrates: Then, on the same day, the Prophet (peace and blessings be upon him) came to me a second time. I said: "O Messenger of Allah (peace and blessings be upon him)! We have been given 'Hais' as a gift, and we have saved it for you." The Prophet (peace and blessings be upon him) said: "Present it." So the Prophet (peace and blessings be upon him) had been fasting, but then he broke his fast.