Sunan Abi Dawud Book 42, Hadith 68
There is no one who will be overtaken by trial regarding whom I do not fear except Muhammad ibn Maslamah, for I heard the Messenger of Allah (ﷺ) say: Trial will not harm you.
The Messenger of Allah (ﷺ) said to al-Hasan ibn Ali. This son of mine is a Sayyid (chief), and I hope Allah may reconcile two parties of my community by means of him. Hammad's version has: And perhaps Allah may reconcile two large parties of Muslims by means of him.
We entered upon Hudhaifah. He said: I know a man whom the trails will not harm. We came out and found that a tent was pitched. We entered and found in it Muhammad b. Maslamah. We asked him about it. He said : I do not intent that any place of your towns should occupy me until that which is prevailing is removed.