Narrated Aisha, Ummul Mu'minin: The Messenger of Allah (ﷺ) used to count the days in Sha'ban in a manner he did not count any other month; then he fasted when he sighted the new moon of Ramadan; but if the weather was cloudy he counted thirty days and then fasted.

Narrated Aisha, Ummul Mu'minin: The Messenger of Allah (ﷺ) used to count the days in Sha'ban in a manner he did not count any other month; then he fasted when he sighted the new moon of Ramadan; but if the weather was cloudy he counted thirty days and then fasted.

حَدَّثَنَا أَحْمَدُ بْنُ حَنْبَلٍ، حَدَّثَنِي عَبْدُ الرَّحْمَنِ بْنُ مَهْدِيٍّ، حَدَّثَنِي مُعَاوِيَةُ بْنُ صَالِحٍ، عَنْ عَبْدِ اللَّهِ بْنِ أَبِي قَيْسٍ، قَالَ سَمِعْتُ عَائِشَةَ، - رضى الله عنها - تَقُولُ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يَتَحَفَّظُ مِنْ شَعْبَانَ مَا لاَ يَتَحَفَّظُ مِنْ غَيْرِهِ ثُمَّ يَصُومُ لِرُؤْيَةِ رَمَضَانَ فَإِنْ غُمَّ عَلَيْهِ عَدَّ ثَلاَثِينَ يَوْمًا ثُمَّ صَامَ ‏.‏