Hadith 961:147
Surayj narrated to us, al-Hakam ibn Abd al-Malik narrated to us, from Ammar ibn Muhammad al-Absi, from Abd al-Rahman ibn Abi Layla, from Muadh, who said: While the Messenger of Allah (peace and blessings of Allah be upon him) was on one of his journeys, he heard a caller saying: "Allah is the Greatest, Allah is the Greatest." He said: "Upon the natural disposition (fitrah)." He then said: "I bear witness that there is no god but Allah." He said: "He has testified with the testimony of truth." He then said: "I bear witness that Muhammad is the Messenger of Allah." He said: "He has exited the Fire. Look for him, and you will find him either a shepherd tending to his flock in a remote place, or a man with his hunting dogs." They looked for him and found him to be a shepherd whose time for prayer had arrived, so he called out for it.
حدثنا سريج، حدثنا الحكم بن عبد الملك، عن عمار بن محمد العبسي، عن عبد الرحمن بن أبي ليلى، عن معاذ قال: بينما رسول الله صلى الله عليه وسلم في بعض أسفاره إذ سمع مناديا يقول: الله أكبر. الله أكبر فقال: " على الفطرة ". فقال: أشهد أن لا إله إلا الله. فقال: " شهد بشهادة الحق ". قال: أشهد أن محمدا رسول الله. قال: " خرج من النار انظروا فستجدونه إما راعيا معزبا، وإما مكلبا " فنظروه فوجدوه راعيا حضرته الصلاة فنادى بها