The Messenger of Allah ﷺ said, "The best fasting after Ramadan is in the month of Allah, Muharram, and the best prayer after the obligatory prayers is the night prayer."
حدثني قتيبة بن سعيد حدثنا أبو عوانة عن أبي بشر عن حميد بن عبد الرحمن الحميري
قال رسول الله ﷺ أفضل الصيام بعد رمضان شهر الله المحرم وأفضل الصلاة بعد الفريضة صلاة الليل
26 - Muslim also related the hadith of Abu Awana, from Abu Bishr, from Humayd bin Abdul-Rahman al-Himyari, from Abu Hurairah, from the Prophet, peace and blessings be upon him and his family, "The best fasting after Ramadan is Muharram." He said, Shubah differed from him, relating it from Abu Bishr, from Humayd al-Himyari, as a mursal narration from the Prophet, peace and blessings be upon him and his family.