Sunan an-Nasa'i, Hadith 3978 ⓘ
It was narrated from Abu Hurairah that : The Messenger of Allah [SAW] said: "We will fight the people until they say La ilaha illallah. If they say La ilaha illallah then their blood and their wealth become forbidden to us, except for a right that is due, and their reckoning will be with Allah."
أَخْبَرَنَا الْقَاسِمُ بْنُ زَكَرِيَّا بْنِ دِينَارٍ، قَالَ حَدَّثَنَا عُبَيْدُ اللَّهِ بْنُ مُوسَى، قَالَ حَدَّثَنَا شَيْبَانُ، عَنْ عَاصِمٍ، عَنْ زِيَادِ بْنِ قَيْسٍ، عَنْ أَبِي هُرَيْرَةَ، عَنْ رَسُولِ اللَّهِ صلى الله عليه وسلم قَالَ " نُقَاتِلُ النَّاسَ حَتَّى يَقُولُوا لاَ إِلَهَ إِلاَّ اللَّهُ فَإِذَا قَالُوا لاَ إِلَهَ إِلاَّ اللَّهُ حَرُمَتْ عَلَيْنَا دِمَاؤُهُمْ وَأَمْوَالُهُمْ إِلاَّ بِحَقِّهَا وَحِسَابُهُمْ عَلَى اللَّهِ " .
also referenced under: Book 37, Hadith 13 (In-Book) & Volume 5, Book 37, Hadith 3983 (DarusSalam)