Yahya related to me from Malik that Zayd ibn Aslam said, "TheMessenger of Allah, may Allah bless him and grant him peace, stoppedfor a rest one night on the way to Makka and appointed Bilal to wakethem up for the prayer. Bilal slept and everyone else slept and noneof them woke up until the sun had risen. When they did wake up theywere all alarmed. The Messenger of Allah, may Allah bless him andgrant him peace, ordered them to ride out of the valley, saying thatthere was a shaytan in it. So they rode out of the valley and theMessenger of Allah, may Allah bless him and grant him peace, orderedthem to dismount and do wudu and he told Bilal either to call theprayer or to give the iqama. The Messenger of Allah, may Allah blesshim and grant him peace, then led them in the prayer. Noticing theiruneasiness, he went to them and said, 'O people! Allah seized ourspirits (arwah) and if He had wished He would have returned them to usat a time other than this. So if you sleep through the time for aprayer or forget it and then are anxious about it, pray it as if youwere praying it in its time.' The Messenger of Allah, may Allah blesshim and grant him peace, turned to Abu Bakr and said, 'Shaytan came toBilal when he was standing in prayer and made him lie down and lulledhim to sleep like a small boy.' The Messenger of Allah, may Allahbless him and grant him peace, then called Bilal and told him the sameas he had told Abu Bakr. Abu Bakr declared, 'I bear witness that youare the Messenger of Allah.' "
Arabic/English book reference: Book 1, Hadith 26