the Prophet said: "There are no days more beloved to Allah that He be worshipped in them than the ten days of Dhul-Hijjah, fasting every day of them is the equivalent of fasting a year, and standing every night of them (in prayer) is the equivalent of standing on the Night of Qadr."
Jami` at-Tirmidhi Book 8, Hadith 77
← Previous Hadith the Messenger of Allah said: "There are no days in which righteous deeds are more beloved to Allah than those ten days." They said: "O Messenger of Allah! Not even Jihad in Allah Cause?" The Messenger of Allah said: "Not even Jihad in Allah's Cause, unless a man were to out with his self and his wealth and not return from that with anything."

Jami` at-Tirmidhi Book 8, Hadith 76 Next Hadith → the Messenger of Allah said: "Whoever fasts Ramadan, then follows it with six from Shawwal, then that is (equal in reward) to fasting everyday."

Jami` at-Tirmidhi Book 8, Hadith 78