وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ يَحْيَى بْنِ سَعِيدٍ، قَالَ أَخْبَرَنِي عُبَادَةُ بْنُ الْوَلِيدِ بْنِ عُبَادَةَ بْنِ الصَّامِتِ، عَنْ أَبِيهِ، عَنْ جَدِّهِ، قَالَ بَايَعْنَا رَسُولَ اللَّهِ صلى الله عليه وسلم عَلَى السَّمْعِ وَالطَّاعَةِ فِي الْيُسْرِ وَالْعُسْرِ وَالْمَنْشَطِ وَالْمَكْرَهِ وَأَنْ لاَ نُنَازِعَ الأَمْرَ أَهْلَهُ وَأَنْ نَقُولَ أَوْ نَقُومَ بِالْحَقِّ حَيْثُمَا كُنَّا لاَ نَخَافُ فِي اللَّهِ لَوْمَةَ لاَئِمٍ ‏.‏

Yahya related to me from Malik that Yahya ibn Said said, ''Ubadaibn al-Walid ibn Ubada ibn as-Samit informed me from his father thathis grandfather (Ubada) said, 'We made a contract with the Messengerof Allah, may Allah bless him and grant him peace, to hear and obey inease and hardship, enthusiasm and reluctance, and not to dispute withpeople in authority and to speak or establish the truth wherever wewere without worrying about criticism.'" Translation Not Available

Book Ref: Muwatta Imam Malik Book 21 Hadith 966
Web Ref:  Muwatta Imam Malik Book 21 Hadith 5