Musnad Ahmad 1119:20

Al-Hasan ibn Siwar Abu al-Ala narrated to us, he said: Isma'il ibn 'Ayyash narrated to us, from Sulayman ibn Salim, from Yahya ibn Jabir, from 'Awf ibn Malik, he said: I heard the Messenger of Allah, peace and blessings of Allah be upon him, saying: "Allah will not gather two swords against this nation: a sword from among them, and a sword from their enemy."