Sunan an-Nasa'i 3977
سنن النسائي#3977SahihIt was narrated that Abu Hurairah said:"The Messenger of Allah [SAW] said: 'I have been commanded to fight the people until they say La ilaha illallah. If they say it, then their blood and wealth are prohibited for me, except for a right that is due, and their reckoning will be with Allah
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahSahih
Al-AlbaniSahih
Zubair Ali ZaiSahih Muslim
In-book reference: 37:12