Hajj is one of the five pillars of Islam and was made obligatory in the tenth, ninth or sixth year, according to different reports [Ibn Kathir, al Bidayah wa al Nihayah, 5/109]. In the tenth year the Prophet (p.b.u.h.) announced that he intended to perform Hajj; this was the only time that he performed Hajj after the Hijrah to Madinah. The Muslims came from all over the Arabian Peninsula to perform Hajj with him. He left Madinah five days before the end of Dhu al Qa'dah (Ibn Hajar, Fath al Bari, 8/104; Ibn Ishaq, with a Hasan isnad (Sirat Ibn Hisham, 4/272). Ibn Kathir, al Bidayah wa al Nihayah, 5/111. This is the same as Ibn Ishaq’s report. He said, "Its isnad is jayyid.").

Lessons from the First Ten Days of Thul-Hijjah... Paradise Is Valuable

Praise be to Allaah Almighty, and may the peace and blessings of Allaah be upon the most honorable of Prophets and Messengers.

The seasons of goodness are great opportunities for seeking provision for the Hereafter and doing the deeds that bring one closer to Allaah Almighty:
1 – To make much more of voluntary deeds: it is one of the best acts of worship; in the Qudsi Hadeeth : “…and My slave keeps on coming closer to Me through performing voluntary deeds till I love him…” [Al-Bukhaari]
2 – To fast the day of ‘Arafah: fasting the day of ‘Arafah is highly recommended for non-pilgrims; as he said about fasting of ‘Arafah: “I seek from Allaah that it expiates the sins of the preceding year and the coming year.” [Muslim]