Alternative sources for this sermon
(see Bibliography for details of these texts)
Amir al-mu'minin's address to his followers on the battlefield of Siffin. About supporting the weak and the low-spirited during the fightingWhoever among you feels spiritedness of heart during the action and finds any of his comrades feeling disheartened should ward off (the enemies) from him just as he would do from himself, because of the superiority he enjoys over the other, for if Allah had willed He would have made the former also like him. Certainly death is a quick seeker. Neither does the steadfast escape it nor can the runner-away defy it. The best death is to be killed. By Allah in Whose hand (power) lies the life of the son of Abu Talib, certainly a thousand strikings of the sword on me are easier to me than a death in bed which is not in obedience to Allah.
A part of the same sermon
It is as if I see you uttering voices like the rustling sound of lizards! You do not seek your own claims nor do you defend against oppression. You have been let free on the path. He who rushes (into the battle) achieves salvation, while he who lags behind, hesitating, gets destruction.