Sahih Muslim , Book 39, Hadith 139 (In-Book) ⓘ

'Amir b. Rabi'ah reported: 'Umar went to Syria and as he came to Sargh, information was given to him that an epidemic had broken out in Syria. 'Abd al-Rahman b. 'Auf narrated to him that Allah's Messenger had said: When you hear of its presence in a land, don't move towards it, and when it breaks out in a land and you are therein, then don't run away from it. So 'Umar b. Khattab came back from Sargh. Salim b. 'Abdullah reported that 'Umar went back, along with people on hearing the hadith reported on the authority of 'Abd al-Rahman b. 'Auf.

وَحَدَّثَنَا يَحْيَى بْنُ يَحْيَى، قَالَ قَرَأْتُ عَلَى مَالِكٍ عَنِ ابْنِ شِهَابٍ، عَنْ عَبْدِ اللَّهِ بْنِ، عَامِرِ بْنِ رَبِيعَةَ أَنَّ عُمَرَ، خَرَجَ إِلَى الشَّامِ فَلَمَّا جَاءَ سَرْغَ بَلَغَهُ أَنَّ الْوَبَاءَ قَدْ وَقَعَ بِالشَّامِ ‏.‏ فَأَخْبَرَهُ عَبْدُ الرَّحْمَنِ بْنُ عَوْفٍ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏ "‏ إِذَا سَمِعْتُمْ بِهِ بِأَرْضٍ فَلاَ تَقْدَمُوا عَلَيْهِ ‏.‏ وَإِذَا وَقَعَ بِأَرْضٍ وَأَنْتُمْ بِهَا فَلاَ تَخْرُجُوا فِرَارًا مِنْهُ ‏" ‏ ‏.‏ فَرَجَعَ عُمَرُ بْنُ الْخَطَّابِ مِنْ سَرْغَ ‏.‏ وَعَنِ ابْنِ شِهَابٍ عَنْ سَالِمِ بْنِ عَبْدِ اللَّهِ أَنَّ عُمَرَ إِنَّمَا انْصَرَفَ بِالنَّاسِ مِنْ حَدِيثِ عَبْدِ الرَّحْمَنِ بْنِ عَوْفٍ ‏.‏