It has been narrated on the authority of Anas that the Quraish made peace with the Prophet (peace and blessings of Allah be to him). Among them was Suhailibn Amr. The Prophet said to Ali: Write: “In the name of Allah, most Gracious and most Merciful.”Suhail said: As for “Bismillah,” we do not know what is meant by “Bismillah-ir-Rahman-ir-Rahim” (In the name of Allah most Gracious and most Merciful). But write what we understand, i.e. Biismikaallahumma (in thy name, O Allah). Then, the Prophet ﷺsaid: Write: “From Muhammad, the Messenger of Allah.” They said: If we knew that you were the Messenger of Allah, we would follow you. Therefore, write your name and the name of your father. So the Holy Prophet (peace and blessings of Allah be to him) said: Write:“From Muhammad ibn Abdullah.”
They laid the condition on the Prophet (peace and blessings of Allah be to him) that anyone who joined them from the Muslims, the Makkans would not return him, and anyone who joined you (the Muslims) from them, you would send him back to them. The Companions said: Messenger of Allah, should we write this? He said: Yes. One who goes away from us to join them, may Allah keep him away! And one who comes to join us from them (and is sent back) Allah will provide him relief and a way of escape.”
(SahihMuslim)
This is one of the hadiths that narrate the events of the Treaty signed at Hudaibiyah.