Full Sharh — Sahih al-Bukhari 7400
حَدَّثَنَا حَفْصُ بْنُ عُمَرَ، حَدَّثَنَا شُعْبَةُ، عَنِ الأَسْوَدِ بْنِ قَيْسٍ، عَنْ جُنْدَبٍ، أَنَّهُ شَهِدَ النَّبِيَّ صلى الله عليه وسلم يَوْمَ النَّحْرِ صَلَّى ثُمَّ خَطَبَ فَقَالَ " مَنْ ذَبَحَ قَبْلَ أَنْ يُصَلِّيَ فَلْيَذْبَحْ مَكَانَهَا أُخْرَى، وَمَنْ لَمْ يَذْبَحْ فَلْيَذْبَحْ بِاسْمِ اللَّهِ ".
English Translation
Narrated Jundab:That he witnessed the Prophet (ﷺ) on the Day of Nahr. The Prophet (ﷺ) offered prayer and then delivered a sermon saying, "Whoever slaughtered his sacrifice before offering prayer, should slaughter another animal in place of the first; and whoever has not yet slaughtered any, should slaughter a sacrifice and mention Allah's Name while doing so
Source
Sahih al-Bukhari(صحيح البخاري)
Oneness, Uniqueness of Allah (Tawheed)
Hadith Number
7400