Musnad Abu Ya'la al-Mawsili 42:190

Zuhayr narrated to us, Jarir narrated to us, from 'Umarah ibn al-Qa'qa', from 'Abd al-Rahman ibn Abi Nu'm, from Abu Sa'id, who said: 'Ali sent to the Messenger of Allah (may Allah bless him and grant him peace) from Yemen some gold in a tanned leather pouch, which had not been refined. He divided it among four men: Zayd al-Khayl, al-Aqra' ibn Habis, 'Uyaynah ibn Hisn, and 'Alqamah ibn 'Ulathah. Some of the Emigrants (Muhajirun) and Helpers (Ansar) said, "We were more deserving of this than them." This reached him, and it distressed him. He said, "Do you not trust me, while I am the trusted one of the One who is in the heaven? The news of the heaven comes to me morning and evening." Then a man stood up before him with protruding eyes, prominent cheekbones, a raised forehead, a thick beard, a shaved head, and a tucked-up lower garment. He said, "O Messenger of Allah, fear Allah." The Prophet (may Allah bless him and grant him peace) said, "Woe to you! Am I not the most deserving of the people of the earth to fear Allah?" Then he turned away. Khalid, the Sword of Allah, stood up and said, "O Messenger of Allah, shall I strike his neck?" He said, "No, perhaps he prays." He said, "How many pray and say with their tongues what is not in their hearts?" He said, "I have not been commanded to split open the hearts of the people, nor to split open their bellies." The Prophet (may Allah bless him and grant him peace) looked at him as he was turning away and said, "Indeed, there will emerge from the loins of this man a people who recite the Book of Allah, but it will not pass beyond their throats. They will pass through the religion just as an arrow passes through the game." 'Umarah said: I think he said, "If I were to reach them, I would surely kill them with the killing of Thamud."