Muwatta Malik, Book 54, Hadith 1794 (In-Book)

Malik related to me from Abdullah ibn Dinar that Abdullah ibn Umar said, "I saw the Messenger of Allah, may Allah bless him and grant him peace, pointing at the east and saying, 'The cause of dissension is here. The cause of dissension is here, from where the helpers of shaytan arise.' "

حَدَّثَنِي مَالِكٌ، عَنْ عَبْدِ اللَّهِ بْنِ دِينَارٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّهُ قَالَ رَأَيْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يُشِيرُ إِلَى الْمَشْرِقِ وَيَقُولُ ‏ "‏ هَا إِنَّ الْفِتْنَةَ هَا هُنَا إِنَّ الْفِتْنَةَ هَا هُنَا مِنْ حَيْثُ يَطْلُعُ قَرْنُ الشَّيْطَانِ ‏" ‏ ‏.‏

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also referenced under: Book 54, Hadith 29 (USC-MSA)