Udhiyah is what is slaughtered from beasts of cattle during the days of al-Adha due to the coming of ‘Eid as a means of drawing near to Allah, the Most High.
The Muslims have unanimously agreed that Udhiyah is a prescribed act in Islam and the majority of scholars view it as a highly recommended Sunnah. This is due to the statement of the Prophet (may Allah’s salah and salam be upon him), “If you sight the crescent of Dhul-Hijjah, and anyone among you had intended to offer a sacrifice, they must refrain from cutting their hair and nails.” This was reported by Muslim and others. In this Hadith, he referred the matter of sacrificing to one’s desire and wish - which does not indicate obligation.

Likewise, it is authentically reported by al-Bayhaqi that Abu Bakr and ‘Umar (may Allah be pleased with them both) would not offer the Udhiyah out of fear of people believing that it is obligatory to do so. Additionally, Ibn Mas‘ud (may Allah be pleased with him) said, “Indeed, I do not offer the Udhiyah - and I like to make things easy upon you, out of fear that people will believe that it is obligatory.” This was reported by Sa‘id ibn Mansur. Also, Ibn Hazm said, “It has not been authentically reported from any of the Companions that it is obligatory.”
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Udhiyah has four conditions which must be met for it to be considered valid:

1. That the sacrificial animal is among the beasts of cattle which are: camels, cows, and sheep. Other than these are not considered among those which are offered as Udhiyah.
2. These beasts of cattle must reach the Islamically recognised age. For a camel, it must be at least five years of age; cows two years of age; goats a year old; and sheep six months old. If the sacrificial animal is less than these ages, then it cannot be considered valid for Udhiyah according to the consensus of the scholars.
3. These animals must be free from defects which prevent them from being sacrificed.
4. The Udhiyah must take place at the prescribed time of sacrificing.
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A sheep suffices for one person, while a camel and a cow suffice for seven people. In light of this, ‘A'ishah (may Allah be pleased with her) narrated that a ram was brought to the Prophet (may Allah’s salah and salam be upon him) to sacrifice. He took it, placed it on the ground, said: “‘Bismillah' [In the name of Allah]. O Allah, accept this from Muhammad, the Family of Muhammad, and the Ummah of Muhammad, and slaughtered it.’” This was reported by Muslim.
Jabir (may Allah be pleased with him) said, “On the Day of al-Hudaybiyyah, we slaughtered alongside the Messenger of Allah (may Allah’s salah and salam be upon him) a camel on behalf of seven people and a cow on behalf of seven people.” This was reported by Muslim.
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It is a condition that the sacrificial animal is free of any defects.
This is supported by the narration reported by Ahmad and the compilers of as-Sunan from al-Bara’ ibn ‘Azib (may Allah be pleased with him) that the Messenger of Allah (may Allah’s salah and salam be upon him) said, “There are four that will not be accepted as sacrifices: One that is obviously blind in one eye, is obviously ill, has an obvious limp, or is so scrawny that its bones do not have any marrow in them.”

- The one who has an obvious limp is the one who is unable to walk alongside healthy sheep due to the limp it suffers from.
- The one that is obviously blind in one eye is the one who has one eye that has sunk in or is protuding out and thus becomes blind in that eye. As for the one who is blind in both eyes, then its defect is even more worthy of being rejected as a sacrifice due to it.
- The one who is obviously ill is the one upon which the signs of illness are apparent. Such examples include inactiveness, rapid fatigue, a weak appetite, fever which prevents it from grazing, or scabs that spoil its flesh, and other things which are considered to be clear illnesses.
- The one that is scrawny such that its bones do not contain any marrow: this refers to an extremely thin animal whose bones contain no marrow. When an animal is severely emaciated, its marrow disappears; therefore, it is not acceptable for sacrifice according to the unanimous agreement of the scholars.
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What is to be said at the time of slaughtering?

What is legislated is to say “Bismillah [In the Name of Allah] Allahu Akbar [Allah is the Greatest]". Uttering “Bismillah” is obligatory at the time of slaughtering, but as for uttering the Takbir, then it is a Sunnah. To utter “Bismillah” and the Takbir together is from the guidance of the Prophet (may Allah’s salah and salam be upon him). This is in light of the Hadith reported by al-Bukhari and Muslim where Anas said, “The Prophet sacrificed two horned rams, each of which was black and white in colour. He sacrificed them with his own hand. He said “Bismillah” and “Allahu Akbar” when doing so and he placed his foot on their sides.
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The Time of Slaughtering the Sacrificial Animal

- The time for slaughtering a sacrificial animal commences from after the ‘Eid prayer on the Day of Sacrifice due to what has been reported by al-Bukhari and Muslim that al-Bara’ ibn ‘Azib (may Allah be pleased with him) narrated that the Prophet (may Allah's salah and salam be upon him) said, “The first thing that we start our day with today is the prayer, then we return to our homes and sacrifice. Therefore, whoever does the same as this has acted according to our Sunnah. Whoever slaughters before the prayer, then this is simply some meat which they have offered to their family and is not to be considered amongst the sacred rites at all.” Also, al-Bukhari and Muslim report from Jundub ibn Sufyan (may Allah be pleased with him) that the Prophet (may Allah’s salah and salam be upon him) said, “If anyone sacrifices before the prayer, they must sacrifice another animal in place of it; but anyone who does not sacrifice until we have prayed must then sacrifice in the Name of Allah.”

- The time for slaughtering ends at sunset on the third day of at-Tashriq, so based on this, the number of days for slaughtering are four.