Musannaf Ibn Abi Shayba 37:616

Narrated to us Abd al-A’la, from al-Jurayri, from Abu al-’Ala, who said: They said to Mutarrif, "This Abd al-Rahman ibn al-Ash’ath has approached." Mutarrif said, "By Allah, if he is seen between two matters: if he prevails, no religion for Allah will be established, and if he is prevailed over, they will remain humiliated until the Day of Resurrection."