The first ten days of Dhul Hijjah, the final month of the Islamic calendar, hold immense significance in Islam, offering numerous opportunities for Muslims to engage in worship, reflection, and good deeds. This period is highly esteemed in both the Quran and Hadith, making it a time of great spiritual benefit.
The Quran highlights these days in Surah Al-Fajr, where Allah swears by the dawn and the ten nights: "By the dawn; by the ten nights" (Quran 89:1-2). Scholars interpret these ten nights as the first ten days of Dhul Hijjah. The Prophet Muhammad (peace be upon him) emphasized their importance, stating, “There are no days in which righteous deeds are more beloved to Allah than these ten days” (Bukhari).

Several key events in Islamic history occurred during these days: 

• Completion of the Kaaba: 

Prophet Ibrahim and his son Ismail completed the Kaaba's construction during this period.

• Institution of Hajj:

These days encompass the days leading up to and including the Hajj pilgrimage, culminating in the Day of Arafah and Eid al-Adha.

• Sacrifice of Prophet Ibrahim: 

Ibrahim’s willingness to sacrifice his son Ismail, as an act of obedience to Allah, is commemorated during these days, particularly on Eid al-Adha.

Things to Do on the First Ten Days of Dhul Hijjah are:

• Fasting: 

Fasting on these days, especially on the Day of Arafah (9th Dhul Hijjah), is highly recommended. The Prophet (PBUH) said, “Fasting on the Day of Arafah expiates the sins of the past year and the coming year” (Muslim).

• Increased Prayer and Supplication:  

Engage in more Salah, make du’a (supplications), and seek forgiveness.

• Charity and Good Deeds: 

Giving in charity, helping those in need, and performing other good deeds are particularly meritorious during these days.

• Reciting the Quran: 

Spend time in recitation and reflection upon the Quran.

• Dhikr (Remembrance of Allah): 

Frequently recite phrases like "Allahu Akbar" (Allah is the Greatest), "Alhamdulillah" (All praise is due to Allah), and "SubhanAllah" (Glory be to Allah).

• Sacrifice (Qurbani): 

Offer an animal sacrifice on Eid al-Adha to commemorate the sacrifice of Ibrahim (AS).

Important deeds to do on these ten days according to Sunnah are:

• Performing Hajj:  

For those who are able, performing Hajj is a major pillar of Islam. The rites of Hajj are performed from the 8th to the 12th of Dhul Hijjah.

• Attending Eid Prayers:

Performing the Eid al-Adha prayer is a communal obligation that brings Muslims together.

• Family and Community Ties: 

Strengthen bonds with family and community, visit relatives, and maintain good relations.

Fasting during the first nine days, especially on the Day of Arafah, is highly meritorious, serving as a means to attain spiritual purification and closeness to Allah. Additionally, donating while fasting enhances the reward manifold. The combination of fasting and charity is a powerful means of gaining Allah’s pleasure and mercy. The Prophet Muhammad (PBUH) said, "The best of charity is that given in Ramadan" (Tirmidhi), and by analogy, charity in the sacred days of Dhul Hijjah holds immense reward as well. 
In conclusion, the first ten days of Dhul Hijjah offer a profound opportunity for Muslims to elevate their spirituality, perform righteous deeds, and seek Allah’s forgiveness and blessings. Engaging in acts of worship, fasting, prayer, charity, and reflection during these days allows one to gain immense rewards and grow closer to Allah.