I heard Jareer bin Abdullah stand to deliver a sermon on the day Mughira bin Shuba died. He said, "Hold fast to fearing Allah alone, and to dignity and tranquility, until your new governor arrives, for he will be coming to you shortly."Then he said, "Pray for forgiveness for your governor, for he loved to pardon others."Then he said, "Now then, I came to the Messenger of Allah ﷺ and said, 'I pledge allegiance to you upon Islam.' The Messenger of Allah ﷺ said, 'And on the condition that you give sincere counsel to every Muslim.' So I pledged allegiance to him upon this. By the Lord of this mosque, I am indeed a sincere counselor to you all."Then he sought Allah's forgiveness and stepped down.
حدثنا عفان عن أبي عوانة حدثنا
سمعت جرير بن عبد الله قام يخطب يوم توفي المغيرة بن شعبة فقال عليكم باتقاء الله عز وجل والوقار والسكينة حتى يأتيكم أمير فإنما يأتيكم الآن ثم قال اشفعوا لأميركم فإنه كان يحب العفو وقال أما بعد فإني أتيت رسول الله ﷺ فقلت أبايعك على الإسلام فقال رسول الله ﷺ وأشترط على النصح لكل مسلم فبايعته على هذا ورب هذا المسجد إني لكم لناصح جميعا ثم استغفر ونزل
Its isnad is sahih, its narrators are trustworthy and well known. Bukhari narrated it, 1/137, no. 57, Fath, in the Book of Faith, on the saying of the Prophet ﷺ, "Religion is sincere advice," and Muslim, 1/75, no. 56, narrated something similar.