عَنِ ابْنِ عُمَرَ رَضِيَ اللَّهُ عَنْهُمَا أَنَّ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ كَانَ يَنْحَرُ يَوْمَ الْأَضْحَى بِالْمَدِينَةِ قَالَ وَكَانَ إِذَا لَمْ يَنْحَرْ ذَبَحَ
It is narrated from Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) that the Noble Prophet (peace and blessings be upon him) used to perform sacrifice (nahr) in Madinah Munawwarah on the day of Eid al-Adha; if he did not perform nahr, he would slaughter (dhabh).