حَدَّثَنَا حَفْصُ بْنُ عُمَرَ، حَدَّثَنَا شُعْبَةُ، عَنْ عَبْدِ اللَّهِ بْنِ دِينَارٍ، عَنِ ابْنِ عُمَرَ، قَالَ كُنَّا نُبَايِعُ النَّبِيَّ صلى الله عليه وسلم عَلَى السَّمْعِ وَالطَّاعَةِ وَيُلَقِّنُنَا فِيمَا اسْتَطَعْتَ ‏.‏

Narrated Ibn 'Umar: We used to take the oath of allegiance to the Prophet (PBUH) to hear and obey, and he would tell: In What I am able. Translation Not Available

Book Ref: Sunan Abi Dawud Book 20 Hadith 2940
Web Ref:  Sunan Abi Dawud Book 19 Hadith 2934