It is narrated from Hazrat Abu Huraira (may Allah be pleased with him) that a man from the tribe of Aslam presented himself in the court of the Messenger and said, "Last night while I was sleeping, a scorpion stung me." The Noble Prophet (peace and blessings be upon him) said, "If you had recited these words in the evening: 'I seek refuge in the perfect words of Allah from the evil of what He has created,' it would never have harmed you."
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 8880