The Messenger of Allah ﷺ said, "When the great battles take place, Allah will send forth a force of the freed slaves who will be the noblest of the Arabs in horsemanship and the finest of them in weaponry. Through them, Allah will support the religion."
قال رسول الله ﷺ: إذا وقعت الملاحم بعث الله بعثا من الموالي هم أكرم العرب فرسا، وأجوده سلاحا يؤيد الله بهم الدين.
Ibn Majah (4090) narrated it, and Hakim graded it sahih (4/548), both through the route of Uthman bin Abu Atikah, from Sulayman bin Habib Muharibi, from Abu Hurairah, who mentioned it. Hakim said, "Sahih according to the standard of Bukhari." Its chain is hasan because of Uthman bin Abu Atikah, for there is disagreement about him, except that his hadith is hasan apart from his narration from Ali bin Yazid Alhani.