Trials and Fierce Battles (Kitab Al-Fitan Wa Al-Malahim)
Dawud :: Book 35 : Hadith 4264
Narrated Sa'id ibn Zayd:
We were with the Prophet (peace_be_upon_him). He mentioned civil strife (fitnah) and expressed its gravity. We or the people said: Apostle of Allah, if this happens to us it will destroy us. The Apostle of Allah (peace_be_upon_him) said; No. It is enough for you that you would be killed. Sa'id said: I saw that my brethren were killed.