It is a great act of worship for a Muslim possessing a sacrificial animal to offer as a sacrifice on Eid Al-Adha. So a Muslim in such state may not have his hair cut or nails trimmed after it has entered the first days of Dhu'l Hijja

In this regard, Muslim narrated on the authority of Umm Salama who reported (these words) directly from Allah's Messenger (ﷺ): (If anyone has in his possession a sacrificial animal to offer as a sacrifice (on 'Id al-Adha), he should not get his hair cut and nails trimmed after it has entered the first days of Dhu'l Hijja)

At other narration, Umm Salama reported Allah's Apostle (ﷺ) as saying: ( If anyone of you intends to offer sacrifice he should not get his hair cut or nails trimmed.)

This is a sunnah limited to those having ability to offer sacrifice, it has likeness aspect to pilgrims when initiating their Ihram and refrain cutting hair and trimming nails, which is to be observed from the moment of sighting crescent of Dhul-Hijjah until moment of slaughtering sacrifice.

This sunnah makes non-pilgrims who want to offer sacrifice senses the same of pilgrims, thus he be more courageous to offering sacrifice and more closer to Almighty Allah.

This action may stimulate his neighbors who neglect offering sacrifice and thus haste to observe this sunnah.

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