It is narrated from Sayyiduna Waleed bin Waleed (may Allah be pleased with him) that once he submitted in the presence of the Messenger: "O Messenger of Allah! Sometimes I feel an unknown fear." The Prophet (peace and blessings be upon him) said: "When you lie down on your bed, recite these words: 'I seek refuge in the perfect words of Allah from His anger and His punishment and from the evil of His servants and from the whisperings of devils and from their presence.' Nothing will be able to harm you, rather, nothing will even come near you."