Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) narrated: We were with the Prophet (peace and blessings be upon him) at Mina when Surah "Wal-Mursalat" was revealed to him. Just then a snake suddenly appeared. The people tried to catch it, but it got away. Then the Prophet (peace and blessings be upon him) said: "You have been protected from its harm just as it has been protected from your harm."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 10122