Muhammad bin Isma'il bin Ibrahim محمد بن إسماعيل بن إبراهيم بن مقسم · The Book of Jihad

Abu Hurairah told him that the Messenger of Allah said: “I have been commanded to fight the people until they say La ilaha illallah (there is none worthy of worship except Allah). Whoever says La ilaha illallah, his life and his property are safe from me, except by its right (in cases where Islamic laws apply), and his reckoning will be with Allah.”

"I heard the Messenger of Allah (ﷺ) say: 'Whoever guards Ribat (the frontier) in the cause of Allah for one day and one night, he will have (a reward) like that of fasting and praying Qiyam for a month. If he dies he will continue to receive reward for what he did, and he will be kept safe from Al-Fattan, and he will be given provision.'"