Musnad Abu Ya'la al-Mawsili 152:306

Abu Khaythama narrated to us, Hajjaj ibn Muhammad narrated to us, Shayban narrated to us, Mansur narrated to us, from Ibrahim, from Alqama, from Abdullah ibn Mas’ud, who said: We were with the Messenger of Allah, may Allah bless him and grant him peace, in a cave when "By the winds sent forth in succession" (Al-Mursalat) was revealed to him. We began to receive it from him. Then a snake emerged from the side of the cave. He said, "Kill it." We rushed toward it, but it escaped us. He said, "It was protected from your evil, just as you were protected from its evil."