Sahih al-Bukhari 83
صحيح البخاري#83Sahihحَدَّثَنَا إِسْمَاعِيلُ، قَالَ حَدَّثَنِي مَالِكٌ، عَنِ ابْنِ شِهَابٍ، عَنْ عِيسَى بْنِ طَلْحَةَ بْنِ عُبَيْدِ اللَّهِ، عَنْ عَبْدِ اللَّهِ بْنِ عَمْرِو بْنِ الْعَاصِ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم وَقَفَ فِي حَجَّةِ الْوَدَاعِ بِمِنًى لِلنَّاسِ يَسْأَلُونَهُ، فَجَاءَهُ رَجُلٌ فَقَالَ لَمْ أَشْعُرْ فَحَلَقْتُ قَبْلَ أَنْ أَذْبَحَ. فَقَالَ " اذْبَحْ وَلاَ حَرَجَ ". فَجَاءَ آخَرُ فَقَالَ لَمْ أَشْعُرْ، فَنَحَرْتُ قَبْلَ أَنْ أَرْمِيَ. قَالَ " ارْمِ وَلاَ حَرَجَ ". فَمَا سُئِلَ النَّبِيُّ صلى الله عليه وسلم عَنْ شَىْءٍ قُدِّمَ وَلاَ أُخِّرَ إِلاَّ قَالَ افْعَلْ وَلاَ حَرَجَ.
Narrated `Abdullah bin `Amr bin Al `Aas:Allah's Messenger (ﷺ) stopped (for a while near the Jimar) at Mina during his last Hajj for the people and they were asking him questions. A man came and said, "I forgot and got my head shaved before slaughtering the Hadi (sacrificing animal)." The Prophet (ﷺ) said, "There is no harm, go and do the slaughtering now." Then another person came and said, "I forgot and slaughtered (the camel) before Rami (throwing of the pebbles) at the Jamra." The Prophet (ﷺ) said, "Do the Rami now and there is no harm." The narrator added: So on that day, when the Prophet (ﷺ) was asked about anything (as regards the ceremonies of Hajj) performed before or after its due time, his reply was: "Do it (now) and there is no harm
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 3:25