﴿ وَلَمَّا بَرَزُوا۟ لِجَالُوتَ وَجُنُودِهِۦ قَالُوا۟ رَبَّنَآ أَفْرِغْ عَلَيْنَا صَبْرًۭا وَثَبِّتْ أَقْدَامَنَا وَٱنصُرْنَا عَلَى ٱلْقَوْمِ ٱلْكَٰفِرِينَ ﴾

“And when they came face to face with Goliath and his forces, they prayed: "O our Sustainer! Shower us with patience in adversity, and make firm our steps, and succour us against the people who deny the truth!"”

So when they went forth against Goliath and his troops facing them in military columns they said ‘Our Lord pour out upon us patience and make firm our feet by strengthening our hearts for this struggle and grant us victory over the disbelieving folk!’