The Messenger of Allah ﷺ said, "Allah has guaranteed for the one who goes out, going out in His path, driven by nothing except striving in My path, faith in Me, and belief in My messengers, that I will either admit him into Paradise or return him to the dwelling from which he set out, having obtained whatever reward or spoils he gained.By the One in whose hand is Muhammad's soul, no one is wounded in the path of Allah but he will come on the Day of Resurrection in the same state as when he was wounded, the color that of blood, the scent that of musk.By the One in whose hand is Muhammad's soul, were it not that it would be too difficult for the Muslims, I would never stay behind from any expedition setting out to fight in the path of Allah. But I do not have the means to provide mounts for them, nor do they have the means themselves, and it would distress them to be left behind from me.By the One in whose hand is Muhammad's soul, I would love to fight in the path of Allah and be killed, then fight and be killed, then fight and be killed."
قال رسول الله ﷺ: تضمن الله لمن خرج خرج في سبيله لا يخرجه إلا جهادا في سبيلي، وإيمانا بي، وتصديقا برسلي، فهو علي ضامن أن أدخله الجنة، أو أرجعه إلى مسكنه الذي منه نائلا ما نال من أجر أو غنيمة، والذي نفس محمد بيده ما من كلم يكلم في سبيل الله إلا جاء يوم القيامة كهيئته حين كلم، لونه لون دم، وريحه مسك، والذي نفس محمد بيده، لولا أن يشق على المسلمين ما قعدت خلاف سرية تغزو في سبيل الله أبدا، ولكن لا أجد سعة فأحملهم، ولا يجدون سعة، ويشق عليهم أن يتخلفوا عني، والذي نفس محمد بيده لوددت أني أغزو في سبيل الله فأقتل، ثم أغزو فأقتل، ثم أغزو فأقتل.
Bukhari related it in the Book of Faith (36) and Muslim in the Book of Leadership (1876:103), both of them from the hadith of Umara bin Qaqa, from Abu Zura bin Amr bin Jareer, from Abu Hurairah, who said, and then he mentioned it. The wording given is that of Muslim, while Bukhari's wording is abridged.