حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مُحَمَّدِ بْنِ زِيَادٍ ، ثنا عَبْدُ الرَّحْمَنِ بْنُ بِشْرِ بْنِ الْحَكَمِ ، ثنا عَبْدُ الرَّحْمَنِ بْنُ مَهْدِيٍّ ، عَنْ مُعَاوِيَةَ بْنِ صَالِحٍ ، عَنْ عَبْدِ اللَّهِ بْنِ أَبِي قَيْسٍ ، عَنْ عَائِشَةَ ، قَالَتْ : " كَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَتَحَفَّظُ مِنْ هِلالِ شَعْبَانَ مَا لا يَتَحَفَّظُ مِنْ غَيْرِهِ ، ثُمَّ يَصُومُ رَمَضَانَ لِرُؤْيَتِهِ ، فَإِنْ غُمَّ عَلَيْهِ عَدَّ ثَلاثِينَ يَوْمًا ثُمَّ صَامَ " . هَذَا إِسْنَادٌ حَسَنٌ صَحِيحٌ.
Lady Aisha (may Allah be pleased with her) narrates: The Prophet Muhammad (peace be upon him) used to pay as much attention to the crescent of Sha'ban as he did to the crescent of Ramadan. Then he would fast upon sighting the crescent. If it was cloudy, he would complete the count of thirty days and then begin fasting. The chain of this hadith is Hasan Sahih (good and authentic).