The Messenger of Allah ﷺ said to us, "Religion is sincere counsel."We asked, "To whom, Messenger of Allah?"He replied, "To Allah, to His Messenger, to His Book, to the leaders of the Muslims, and to the Muslim community at large."
قال لنا رسول الله ﷺ: الدين النصيحة، قال: قلنا: لمن يا رسول الله؟ قال: لله ولرسوله ولكتابه ولأئمة المسلمين وعامتهم.
Bazzar narrated it in Kashf Astar (62), Darimi (2796), and Tahawi in Sharh Mushkil (1447), all of them through routes going back to Hisham bin Saad, from Zayd bin Aslam and Nafi, from Ibn Umar, who said, and then he related the hadith.Its chain is hasan because of Hisham bin Saad Madani, whose hadith is graded hasan when he does not contradict others and does not bring something that would be rejected from him. His hadith has a firm basis, and this is one of them.Haythami said in Majma (1/87), "Bazzar narrated it, and its narrators are the narrators of the Sahih."The meaning of sincere devotion to Allah, glorified is He, is having sound belief in His oneness and being sincere in intention when worshipping Him. Sincere devotion to the Book of Allah means believing in it and acting upon what is in it. Sincere devotion to His Messenger means affirming his prophethood and giving him full obedience in what he commanded and what he forbade. Sincere devotion to the leaders of the believers means obeying them in what is right, and not regarding rebellion against them by the sword as permissible even if they act unjustly. Sincere devotion to the Muslims in general means guiding them toward what benefits them.Khattabi mentioned this in Maalim Sunan.