Musannaf Ibn Abi Shayba 18:1245

Abu Bakr narrated to us, he said: Abu al-Ashhab narrated to us, from al-Hasan, who said: The Messenger of Allah (may Allah bless him and grant him peace) said: "The blood of the Muslims is equal in value. The lowest of them strives for their protection (dhimmah), and they are a single hand against those who are other than them."