as we are approaching raya haji...here is a bit about 10 days of zulhijjah...
"THERE are no days during which good deeds are more beloved by Allah than these (ten) days." (Al-Bukhari, Tirmidhi and others)
The Prophet (peace be upon him) was then asked: "Not even Jihad in Allah's way?" He replied: "Not even Jihad in Allah's way; except for a person who went out (for Jihad) with his self and wealth and came back with none (i.e. lost all for Allah)." (Tirmidhi – authenticated in Al-Albani's Irwaa' Al-Ghaleel no. 953)
All good deeds can be done during these days and the early generations of Muslims used to exert themselves excessively in worshipping Allah. Fasting and Dhikr (glorifying and remembering Allah) especially should be done in plenty.
Ibn Abbas commented on the verse "…and to mention Allah's name (plentifully) on known days" (Qur'an, 22:28) by saying: "…these known days are the Ten Days (of Dhul Hijjah)." (Tafseer Ibn Katheer)
One of the wives of the Prophet (peace be upon him) said: "Allah's Messenger used to fast the (first) nine days of Dhul Hijjah, the day of `Ashouraa', and three days of each month. (Saheeh Sunan Abu Dawood no. 2129)
Fasting on all these days, however, is not Wajib (compulsory) , nor is it a stressed Sunnah that the Messenger (peace be upon him) never left. Ayesha said: "I never saw the Messenger (peace be upon him) fast the ten days." (Saheeh Muslim)
Best day of the year
On the day of Arafah the pilgrims stand in worship in the Mountain of Arafah.
"Fasting the day of Arafah expiates the (minor) sins of two years: a past one and a coming one. And fasting the day of `Aashouraa' expiates the sins of the past year." (Saheeh Muslim)
"There is no day on which Allah frees people from the Fire as He does on the day of Arafah. (Saheeh Muslim)
Day of Sacrifice
The tenth of Dhul-Hijjah is Eid Al-Adha or the day of An-Nahr (sacrifice). It marks the conclusion of the major rites of Haj, and commemorates Allah's bounty on His Messenger Ibrahim, when He gave him a ram to sacrifice as ransom in exchange for his son Ismail (peace be upon them).
"The day of Al-Fitr (i.e. Eid Al-Fitr), the day of An-Nahr, and the days of Tashreeq are Eid days for us Muslims. They are days of eating and drinking." (Ahmad, An-Nasaa'ee, Saheeh Al-Jaami no. 8192)
Three days after Eid
On these days, the pilgrims complete their rites, Muslims continue with their Eid celebrations, and are prohibited to fast. "The days of Tashreeq are days of eating, drinking and remembering Allah." (Saheeh Muslim)
The consensus of Muslim scholars is that the sacrifice is an important Sunnah, and a worship called for in the Law of Allah. However, they differ as to whether it is Nafl (voluntary) or Wajib (mandatory) for those who can afford it. Some scholars have explained the different Ahadith on the subject by stating that the sacrifice is obligatory on those who can afford it and not obligatory on those who cannot.
Abu Hurayrah reported that the Messenger (peace be upon him) said: "He who has the capacity, and does not sacrifice, may not approach our Musalla (place of prayer - on the Eid)." (Ibn Maajah, Ahmad and others, authenticated by Al-Albani in Saheeh Sunan Ibn Majah no. 2533)
One who wants to sacrifice (Udhiyyah) should not cut his hair or nails during these 10 days. He should do so before these 10 days. The Prophet (peace be upon him) said, "When anyone of you intending to sacrifice the animal enters the month of Dhul Hijjah he should not get his hair or nails touched (cut)." (Saheeh Muslim)