It is narrated from Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) mentioned the day of Ashura and spoke of its great importance. Then he said to the people around him: "Whoever among you has not eaten anything (yet) should fast this day, and whoever has eaten something should also refrain (from food and drink like a fasting person) for the rest of his day."
No one narrated this hadith from Qaza'ah (may Allah have mercy on him) except Yazid (may Allah have mercy on him).
Hadith Referenceالمعجم الأوسط / باب الباء / 3231
Hadith Gradingمحدثین:رجاله ثقات
Hadith Takhrij«قال بدر الدين العيني: رجاله ثقات «عمدة القاري شرح صحيح البخاري، ج 11، ص 120»» «قال الهيثمي: رجاله ثقات «مجمع الزوائد ومنبع الفوائد، ج 3، ص 186»» «أخرجه الطحاوي فى «شرح مشكل الآثار» برقم: 2274»