عَنْ ثَابِتٍ عَنْ أَنَسٍ رَضِيَ اللَّهُ عَنْهُ قَالَ كَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ يُغِيرُ عِنْدَ طُلُوعِ الْفَجْرِ فَيَسْتَمِعُ فَإِذَا سَمِعَ أَذَانًا أَمْسَكَ وَإِلَّا أَغَارَ قَالَ فَتَسَمَّعَ ذَاتَ يَوْمٍ قَالَ فَسَمِعَ رَجُلًا يَقُولُ اللَّهُ أَكْبَرُ اللَّهُ أَكْبَرُ فَقَالَ عَلَى الْفِطْرَةِ فَقَالَ أَشْهَدُ أَنْ لَا إِلَهَ إِلَّا اللَّهُ فَقَالَ خَرَجْتَ مِنَ النَّارِ
It is narrated from Sayyiduna Anas (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) would launch a raid after the break of dawn. He (peace and blessings be upon him) would listen attentively; if he heard the sound of the adhan, he would stop, otherwise he would attack. One day, he (peace and blessings be upon him) was listening attentively. When he (peace and blessings be upon him) heard the muezzin say: "Allahu Akbar, Allahu Akbar," he (peace and blessings be upon him) said: "They are upon the natural disposition (fitrah)." Then, when the muezzin said: "Ashhadu an la ilaha illallah," he (peace and blessings be upon him) said: "He has been saved from the Fire."