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كتاب الاعتصام بالكتاب والسنة
96
Holding Fast to the Qur'an and Sunnah
Sahih al-Bukhari 7272

Narrated `Abdullah bin Dinar:

`Abdullah Bin `Umar wrote to `Abdul Malik bin Marwan, swearing allegiance to him: 'I swear allegiance to you in that I will listen and obey what is in accordance with the Laws of Allah and the Tradition of His Apostle as much as I can.'

حَدَّثَنَا إِسْمَاعِيلُ، حَدَّثَنِي مَالِكٌ، عَنْ عَبْدِ اللَّهِ بْنِ دِينَارٍ، أَنَّ عَبْدَ اللَّهِ بْنَ عُمَرَ، كَتَبَ إِلَى عَبْدِ الْمَلِكِ بْنِ مَرْوَانَ يُبَايِعُهُ، وَأُقِرُّ لَكَ بِالسَّمْعِ وَالطَّاعَةِ عَلَى سُنَّةِ اللَّهِ وَسُنَّةِ رَسُولِهِ، فِيمَا اسْتَطَعْتُ‏.‏
Reference : Sahih al-Bukhari 7272
In-book reference : Book 96, Hadith 5
USC-MSA web (English) reference : Vol. 9, Book 92, Hadith 377
  (deprecated numbering scheme)