كتاب الاعتصام بالكتاب والسنة
Holding Fast to the Qur'an and Sunnah
Chapter: Following the Sunna of the Prophet (saws)
باب الاِقْتِدَاءِ بِسُنَنِ رَسُولِ اللَّهِ صلى الله عليه وسلم
Sahih al-Bukhari 7283

Narrated Abu Musa:

The Prophet (ﷺ) said, "My example and the example of what I have been sent with is that of a man who came to some people and said, 'O people! I have seen the enemy's army with my own eyes, and I am the naked warner; so protect yourselves!' Then a group of his people obeyed him and fled at night proceeding stealthily till they were safe, while another group of them disbelieved him and stayed at their places till morning when the army came upon them, and killed and ruined them completely So this is the example of that person who obeys me and follows what I have brought (the Qur'an and the Sunna), and the example of the one who disobeys me and disbelieves the truth I have brought."

حَدَّثَنَا أَبُو كُرَيْبٍ، حَدَّثَنَا أَبُو أُسَامَةَ، عَنْ بُرَيْدٍ، عَنْ أَبِي بُرْدَةَ، عَنْ أَبِي مُوسَى، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ ‏ "‏ إِنَّمَا مَثَلِي وَمَثَلُ مَا بَعَثَنِي اللَّهُ بِهِ كَمَثَلِ رَجُلٍ أَتَى قَوْمًا فَقَالَ يَا قَوْمِ إِنِّي رَأَيْتُ الْجَيْشَ بِعَيْنَىَّ، وَإِنِّي أَنَا النَّذِيرُ الْعُرْيَانُ فَالنَّجَاءَ‏.‏ فَأَطَاعَهُ طَائِفَةٌ مِنْ قَوْمِهِ فَأَدْلَجُوا، فَانْطَلَقُوا عَلَى مَهَلِهِمْ فَنَجَوْا، وَكَذَّبَتْ طَائِفَةٌ مِنْهُمْ فَأَصْبَحُوا مَكَانَهُمْ، فَصَبَّحَهُمُ الْجَيْشُ، فَأَهْلَكَهُمْ وَاجْتَاحَهُمْ، فَذَلِكَ مَثَلُ مَنْ أَطَاعَنِي، فَاتَّبَعَ مَا جِئْتُ بِهِ، وَمَثَلُ مَنْ عَصَانِي وَكَذَّبَ بِمَا جِئْتُ بِهِ مِنَ الْحَقِّ ‏"‏‏.‏
Reference : Sahih al-Bukhari 7283
In-book reference : Book 96, Hadith 15
USC-MSA web (English) reference : Vol. 9, Book 92, Hadith 387
  (deprecated numbering scheme)