Muwatta Malik, Book 54, Hadith 1780 (In-Book)

Malik related to me from Abu'z-Zinad from al-Araj from Abu Hurayra that the Messenger of Allah, may Allah bless him and grant him peace, said, "The head of kufr is towards the east. Boasting and price is among people who have horses and camels. The loud-voiced people are the people of tents (the Bedouins). Tranquillity is with the people who have sheep."

حَدَّثَنِي مَالِكٌ، عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏ "‏ رَأْسُ الْكُفْرِ نَحْوَ الْمَشْرِقِ وَالْفَخْرُ وَالْخُيَلاَءُ فِي أَهْلِ الْخَيْلِ وَالإِبِلِ وَالْفَدَّادِينَ أَهْلِ الْوَبَرِ وَالسَّكِينَةُ فِي أَهْلِ الْغَنَمِ ‏" ‏ ‏.‏

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also referenced under: Book 54, Hadith 15 (USC-MSA)