Arabic (Original)
حَدَّثَنَا يَحْيَى بْنُ سَعِيدٍ عَنْ عُبَيْدِ اللَّهِ حَدَّثَنِي نَافِعٌ عَنِ ابْنِ عُمَرَ قَالَ قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ الشَّهْرُ تِسْعٌ وَعِشْرُونَ هَكَذَا وَهَكَذَا فَإِنْ غُمَّ عَلَيْكُمْ فَاقْدُرُوا لَهُ قَالَ وَكَانَ ابْنُ عُمَرَ إِذَا كَانَ لَيْلَةُ تِسْعٍ وَعِشْرِينَ وَكَانَ فِي السَّمَاءِ سَحَابٌ أَوْ قَتَرٌ أَصْبَحَ صَائِمًا.
English Translation
Yahya ibn Sa'id narrated to us, from 'Ubaydullah: Nafi' told me, from Ibn 'Umar, who said: The Messenger of Allah, peace and blessings be upon him, said: "The month is twenty-nine [days], like this and like this; but if it is obscured for you, then estimate for it." He said: And Ibn 'Umar, if it was the twenty-ninth night and there was cloud or haze in the sky, would begin the day fasting.