Sahih al-Bukhari 19
Sahih al-Bukhari · Book 2: Belief · To flee (run away) from Al-Fitn (afflictions and trials), is a part of religion
Narrated Abu Said Al-Khudri:
حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مَسْلَمَةَ ، عَنْ مَالِكٍ ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ عَبْدِ اللَّهِ بْنِ عَبْدِ الرَّحْمَنِ بْنِ أَبِي صَعْصَعَةَ ، عَنْ أَبِيهِ ، عَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ ، أَنَّهُ قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " يُوشِكُ أَنْ يَكُونَ خَيْرَ مَالِ الْمُسْلِمِ غَنَمٌ يَتْبَعُ بِهَا شَعَفَ الْجِبَالِ وَمَوَاقِعَ الْقَطْرِ، يَفِرُّ بِدِينِهِ مِنَ الْفِتَنِ " .
Allah's Messenger (ﷺ) said, "A time will soon come when the best property of a Muslim will be sheep which he will take on the top of mountains and the places of rainfall (valleys) so as to flee with his religion from afflictions."