Sahih Bukhari | Volume 6 | Hadith Number 456

Narrated by Abdullah
While we were with the Prophet in a cave, Surat wal-Mursalat was revealed to him and he recited it, and I heard it directly from his mouth as soon as he recited its revelation. Suddenly a snake sprang at us, and the Prophet said, "Kill it!" We ran to kill it but it escaped quickly. The Prophet said. "It has escaped your evil, and you too have escaped its evil."