Ali bin Abu Talib reported,

The Messenger of Allah ﷺ did not entrust me with anything beyond what he gave the people, except for what is written on a sheet kept in the sheath of my sword. They kept pressing him until he produced the sheet, and on it was written, "The believers' lives are equal in retaliation. The protection granted by the lowest among them is binding upon them all, and they stand united against any outsider. A believer is not to be killed in retaliation for a disbeliever, nor is one under a covenant to be killed during the term of his covenant."

Nasai 4749

Sahih

أخبرنا محمد بن بشار قال حدثنا الحجاج بن منهال قال حدثنا همام عن قتادة عن أبي حسان قال

قال عل

ي ما عهد إلي رسول الله ﷺ بشيء دون الناس إلا في صحيفة في قراب سيفي فلم يزالوا به حتى أخرج الصحيفة فإذا فيها المؤمنون تكافأ دماؤهم يسعى بذمتهم أدناهم وهم يد على من سواهم لا يقتل مؤمن بكافر ولا ذو عهد في عهده

النسائي 4749صحيح
Contents
Reference
Commentary
Ayat
Collection
Sunan Nasai Sughra
Book
Sworn testimony
Chapter
Dropping of retaliation from a Muslim for a disbeliever
Numbering
Darussalam 4749
Nasai 4749