The Excellence of As-Saum (The Fast) during the first ten Days of Dhul-Hijjah

باب فضل الصوم وغيره في العشر الأول من ذي الحجة‏:‏

This short chapter lifts up the first ten days of the month of Dhul-Hijjah as a uniquely precious time for good deeds. It encourages believers to seize these days with righteous action.

The single hadith makes a striking point: no days hold deeds more beloved to Allah than these, ranking them even above the great act of striving in Allah's cause, with a rare exception. The takeaway is to make these early days of the month especially full of worship and good.

Hadith 1249

Ibn 'Abbas (May Allah be pleased with them) reported:

وعن ابن عباس رضي الله عنهما قال‏:‏ قال رسول الله صلى الله عليه وسلم‏:‏ ‏"‏ ما من أيام العمل الصالح فيها أحب إلى الله من هذه الأيام‏"‏ يعني أيام العشر، قالوا‏:‏ يا رسول الله ولا الجهاد في سبيل الله‏؟‏ قال‏:‏ ‏"‏ولا الجهاد في سبيل الله، إلا رجل خرج بنفسه، وماله فلم يرجع من ذلك بشيء‏"‏ ‏(‏‏(‏رواه البخاري‏)‏‏)‏‏.‏

The Messenger of Allah (ﷺ) said, "There are no days during which the righteous action is so pleasing to Allah than these days (i.e., the first ten days of Dhul-Hijjah)." He was asked: "O Messenger of Allah, not even Jihad in the Cause of Allah?" He (ﷺ) replied, "Not even Jihad in the Cause of Allah, except in case one goes forth with his life and his property and does not return with either of it." [Al- Bukhari].

In plain words

Righteous deeds in the first ten days of Dhul-Hijjah are more beloved to Allah than in any other days, ranked even above striving in His cause, save for the one who gives his life and wealth and returns with neither.

Reference : Riyad as-Salihin 1249 In-book reference : Book 8, Hadith 259