Narrated 'Abdullah bin 'Amir bin Rabi'a:

'Umar bin Al-Khattab left for Sham, and when he reached a placed called Sargh, he came to know that there was an outbreak of an epidemic (of plague) in Sham. Then 'AbdurRahman bin 'Auf told him that Allah's Apostle ﷺ said, "If you hear the news of an outbreak of an epidemic (plague) in a certain place, do not enter that place: and if the epidemic falls in a place while you are present in it, do not leave that place to escape from the epidemic." So 'Umar returned from Sargh.

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مَسْلَمَةَ، عَنْ مَالِكٍ، عَنِ ابْنِ شِهَابٍ، عَنْ عَبْدِ اللَّهِ بْنِ عَامِرِ بْنِ رَبِيعَةَ، أَنَّ عُمَرَ بْنَ الْخَطَّابِ ـ رضى الله عنه ـ خَرَجَ إِلَى الشَّأْمِ، فَلَمَّا جَاءَ بِسَرْغَ بَلَغَهُ أَنَّ الْوَبَاءَ وَقَعَ بِالشَّأْمِ فَأَخْبَرَهُ عَبْدُ الرَّحْمَنِ بْنُ عَوْفٍ أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ " إِذَا سَمِعْتُمْ بِأَرْضٍ فَلاَ تَقْدَمُوا عَلَيْهِ، وَإِذَا وَقَعَ بِأَرْضٍ وَأَنْتُمْ بِهَا فَلاَ تَخْرُجُوا فِرَارًا مِنْهُ ". فَرَجَعَ عُمَرُ مِنْ سَرْغَ. وَعَنِ ابْنِ شِهَابٍ عَنْ سَالِمِ بْنِ عَبْدِ اللَّهِ أَنَّ عُمَرَ إِنَّمَا انْصَرَفَ مِنْ حَدِيثِ عَبْدِ الرَّحْمَنِ.