And when they went forth to [face] Goliath and his soldiers, they said, “Our Lord, pour upon us patience and plant firmly our feet and give us victory over the disbelieving people.”
Tatkala Jalut dan tentaranya telah nampak oleh mereka, merekapun (Thalut dan tentaranya) berdoa: “Ya Tuhan kami, tuangkanlah kesabaran atas diri kami, dan kokohkanlah pendirian kami dan tolonglah kami terhadap orang-orang kafir”.
(pic taken from here)
This is a du’a that can be found in Holy Qur’an. And there are so many du’a we can learn, memorize, and recite from it. I just knew this fact several days ago when reading Qur’an verses with the translations in Indonesian :).