Yahya related to me from Malik from Yahya ibn Said that Umar ibnal-Khattab said, "The nobility of the mumin is his taqwa. His deen ishis noble descent. His manliness is his good character. Boldness andcowardice are but instincts which Allah places wherever He wills. Thecoward shrinks from defending even his father and mother, and the boldone fights for the sake of the combat not for the spoils. Being slainis but one way of meeting death, and the martyr is the one who giveshimself, expectant of reward from Allah."
USC-MSA web (English) reference: Book 21, Hadith 35
Arabic reference: Book 21, Hadith 996