It is narrated from Sayyiduna Wahshi bin Harb (may Allah be pleased with him) that Sayyiduna Abu Bakr (may Allah be pleased with him) appointed Sayyiduna Khalid bin Walid (may Allah be pleased with him) against the apostates and said: I heard the Messenger of Allah (peace and blessings be upon him) say, "Khalid bin Walid (may Allah be pleased with him) is the best servant of Allah and the best individual of the people. He is one of the swords of Allah, which Allah Almighty has unleashed upon the disbelievers and the hypocrites."