Sunan an Nasai
3972
Sahih Mutawatir+2

Abu Hurairah narrated that :The Messenger of Allah [SAW] said: "I have been commanded to fight the people until they say La ilaha illallah (there is none worthy of worship but Allah). Whoever says La ilaha illallah, his wealth and his life are safe from me except for a right that is due, and his reckoning will be with Allah

Sahih MutawatirAbu Ghuddah
Sahih MutawatirAl-Albani