Sayyiduna Anas (may Allah be pleased with him) narrates that some people from Yemen came to the Messenger of Allah (peace and blessings be upon him) and said: "Send with us a man who will teach us the Sunnah and Islam." He took the hand of Sayyiduna Abu Ubaidah (may Allah be pleased with him) and said: "He is the trustworthy one of this Ummah."