When Amir al-mu'minin decided to fight the enemy face to face at Siffin he said:
O My God! Sustainer of the high sky and the suspended firmament which Thou hast made a shelter for the night and the day, an orbit for the sun and the moon and a path for the rotating stars, and for populating it Thou hast created a group of Thy angels who do not get weary of worshipping Thee. O Sustainer of this earth which Thou hast made an abode for people and a place for the movement of insects and beasts and countless other creatures seen and unseen. 
O Sustainer of strong mountains which Thou hast made as pegs for the earth and (a means of) support for people. If Thou givest us victory over our enemy, save us from excesses and keep us on the straight path of truth. But if Thou givest them victory over us, then grant us martyrdom and save us from mischief.
Where are those who protect honour, and those self-respecting persons who defend respectable persons in the time of hardship? Shame is behind you while Paradise is in front of you.
(1) Nasr ibn Muzahim, Siffin, 232;
(2) al-Tabari, Ta'rikh, VI, 8, events of 37 H.;