عَنْ عِكْرِمَةَ قَالَ: سَمِعْتُ ابْنَ عَبَّاسَ رَضِيَ اللَّهُ عَنْهُمَا يَقُولُ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ: ((صُومُوا لِرُؤْيَتِهِ وَأَفْطِرُوا لِرُؤْيَتِهِ، فَإِنْ حَالَ بَيْنَكُمْ وَبَيْنَهُ سَحَابٌ فَكَمِّلُوا الْعِدَّةَ ثَلَاثِينَ، وَلَا تَسْتَقْبِلُوا الشَّهْرَ اسْتِقْبَالًا))، قَالَ حَاتِمٌ: يَعْنِي عِدَّةَ شَعْبَانَ
It is narrated from Sayyiduna Abdullah bin Abbas (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: Begin fasting by sighting the moon and stop fasting by sighting the moon. If clouds come between you and the moon, then complete the count (thirty) of the previous month, and do not fast just before (the arrival of) the month of Ramadan. Hatim, the narrator, says: The Prophet (peace and blessings be upon him) meant that the count of Sha'ban should be completed.