It was narrated that Zaid bin Arqam said: “The Companions of the Messenger of Allah (ﷺ) said: ‘O Messenger of Allah, what are these sacrifices?’ He said: ‘The Sunnah of your father Ibrahim.’ They said: ‘What is there for us in them, O Messenger of Allah?’ He said: ‘For every hair, one merit.’ They said: ‘What about wool, O Messenger of Allah?’ He said: ‘For every hair of wool, one merit.’”
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا مُحَمَّدُ بْنُ خَلَفٍ الْعَسْقَلاَنِيُّ، حَدَّثَنَا آدَمُ بْنُ أَبِي إِيَاسٍ، حَدَّثَنَا سَلاَّمُ بْنُ مِسْكِينٍ، حَدَّثَنَا عَائِذُ اللَّهِ، عَنْ أَبِي دَاوُدَ، عَنْ زَيْدِ بْنِ أَرْقَمَ، قَالَ قَالَ أَصْحَابُ رَسُولِ اللَّهِ ـ صلى الله عليه وسلم ـ يَا رَسُولَ اللَّهِ مَا هَذِهِ الأَضَاحِيُّ قَالَ " سُنَّةُ أَبِيكُمْ إِبْرَاهِيمَ " . قَالُوا فَمَا لَنَا فِيهَا يَا رَسُولَ اللَّهِ قَالَ " بِكُلِّ شَعَرَةٍ حَسَنَةٌ " . قَالُوا فَالصُّوفُ يَا رَسُولَ اللَّهِ قَالَ " بِكُلِّ شَعَرَةٍ مِنَ الصُّوفِ حَسَنَةٌ " .
sunnah.com