Musnad Ahmad

Qais bin ‘Abad says that once I and Ashtar went to the service of Sayyiduna ‘Ali (may Allah be pleased with him) and asked him: Is there anything that the Messenger of Allah (peace and blessings be upon him) specifically advised you about, which was not included for the general people? He replied: The Prophet (peace and blessings be upon him) did not give me any special advice apart from the people, but whatever I heard from the Prophet (peace and blessings be upon him), I wrote it in a scroll and kept it in the sheath of my sword. He took it out, and it was written in it: “The lives of the Muslims are equal among themselves; if even the lowest among them grants protection to someone, his protection will be respected. And the Muslims are like a single hand against others. Beware! No Muslim should be killed in exchange for a disbeliever, and no dhimmi should be killed as long as he is within the period of the treaty and abides by its conditions.” Also, it was written: “Whoever invents a bid‘ah (innovation) or shelters a person of bid‘ah, upon him is the curse of Allah, the angels, and all people.”