Sahih Bukhari
Tricks
Volume: 009 / Book Number: 086 / Hadith Number: 103
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 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.