Ibn ‘Abbaas (may Allaah be pleased with him and his father) reported that the Prophet (peace and blessings of Allaah be upon him) said: “There are no days in which righteous deeds are more beloved to Allaah than these ten days.” The people asked, “Not even jihaad for the sake of Allaah?” He said, “Not even jihaad for the sake of Allaah, except in the case of a man who went out to fight giving himself and his wealth up for the cause, and came back with nothing.” (Reported by al-Bukhaari, 2/457).

Is fasting one day in first ten days of Dul hijjah equal to fasting one year? Is this hadith of tirmidhi authentic? -“The Prophet (peace and blessings of Allaah be upon him) used to fast on the ninth of Dhu’l-Hijjah, on the day of ‘Aashooraa’, on three days of each month, and on the first two Mondays and Thursdays of each month.” (Reported by al-Nisaa’i, 4/205 and by Abu Dawud; classified by al-Albaani as saheeh in Saheeh Abi Dawud, 2/462).