2:249
فَلَمَّا فَصَلَ طَالُوتُ بِٱلْجُنُودِ قَالَ إِنَّ ٱللَّهَ مُبْتَلِيكُم بِنَهَرٍ فَمَن شَرِبَ مِنْهُ فَلَيْسَ مِنِّى وَمَن لَّمْ يَطْعَمْهُ فَإِنَّهُۥ مِنِّىٓ إِلَّا مَنِ ٱغْتَرَفَ غُرْفَةًۢ بِيَدِهِۦ ۚ فَشَرِبُوا۟ مِنْهُ إِلَّا قَلِيلًا مِّنْهُمْ ۚ فَلَمَّا جَاوَزَهُۥ هُوَ وَٱلَّذِينَ ءَامَنُوا۟ مَعَهُۥ قَالُوا۟ لَا طَاقَةَ لَنَا ٱلْيَوْمَ بِجَالُوتَ وَجُنُودِهِۦ ۚ قَالَ ٱلَّذِينَ يَظُنُّونَ أَنَّهُم مُّلَـٰقُوا۟ ٱللَّهِ كَم مِّن فِئَةٍ قَلِيلَةٍ غَلَبَتْ فِئَةً كَثِيرَةًۢ بِإِذْنِ ٱللَّهِ ۗ وَٱللَّهُ مَعَ ٱلصَّـٰبِرِينَ
And when Saul went forth with the soldiers, he said, "Indeed, Allah will be testing you with a river. So whoever drinks from it is not of me, and whoever does not taste it is indeed of me, excepting one who takes [from it] in the hollow of his hand." But they drank from it, except a [very] few of them. Then when he had crossed it along with those who believed with him, they said, "There is no power for us today against Goliath and his soldiers." But those who were certain that they would meet Allah said, "How many a small company has overcome a large company by permission of Allah. And Allah is with the patient."
Context in Surah Al-Baqarah
Nearby ayahs help place verse 2:249 in sequence and meaning.
وَقَالَ لَهُمْ نَبِيُّهُمْ إِنَّ ٱللَّهَ قَدْ بَعَثَ لَكُمْ طَالُوتَ مَلِكًا ۚ قَالُوٓا۟ أَنَّىٰ يَكُونُ لَهُ ٱلْمُلْكُ عَلَيْنَا وَنَحْنُ أَحَقُّ بِٱلْمُلْكِ مِنْهُ وَلَمْ يُؤْتَ سَعَةً مِّنَ ٱلْمَالِ ۚ قَالَ إِنَّ ٱللَّهَ ٱصْطَفَىٰهُ عَلَيْكُمْ وَزَادَهُۥ بَسْطَةً فِى ٱلْعِلْمِ وَٱلْجِسْمِ ۖ وَٱللَّهُ يُؤْتِى مُلْكَهُۥ مَن يَشَآءُ ۚ وَٱللَّهُ وَٰسِعٌ عَلِيمٌ
And their prophet said to them, "Indeed, Allah has sent to you Saul as a king." They said, "How can he have kingship over us while we are more worthy of kingship than him and he has not been given any measure of wealth?" He said, "Indeed, Allah has chosen him over you and has increased him abundantly in knowledge and stature. And Allah gives His sovereignty to whom He wills. And Allah is all-Encompassing [in favor] and Knowing."
وَقَالَ لَهُمْ نَبِيُّهُمْ إِنَّ ءَايَةَ مُلْكِهِۦٓ أَن يَأْتِيَكُمُ ٱلتَّابُوتُ فِيهِ سَكِينَةٌ مِّن رَّبِّكُمْ وَبَقِيَّةٌ مِّمَّا تَرَكَ ءَالُ مُوسَىٰ وَءَالُ هَـٰرُونَ تَحْمِلُهُ ٱلْمَلَـٰٓئِكَةُ ۚ إِنَّ فِى ذَٰلِكَ لَـَٔايَةً لَّكُمْ إِن كُنتُم مُّؤْمِنِينَ
And their prophet said to them, "Indeed, a sign of his kingship is that the chest will come to you in which is assurance from your Lord and a remnant of what the family of Moses and the family of Aaron had left, carried by the angels. Indeed in that is a sign for you, if you are believers."
وَلَمَّا بَرَزُوا۟ لِجَالُوتَ وَجُنُودِهِۦ قَالُوا۟ رَبَّنَآ أَفْرِغْ عَلَيْنَا صَبْرًا وَثَبِّتْ أَقْدَامَنَا وَٱنصُرْنَا عَلَى ٱلْقَوْمِ ٱلْكَـٰفِرِينَ
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."
فَهَزَمُوهُم بِإِذْنِ ٱللَّهِ وَقَتَلَ دَاوُۥدُ جَالُوتَ وَءَاتَىٰهُ ٱللَّهُ ٱلْمُلْكَ وَٱلْحِكْمَةَ وَعَلَّمَهُۥ مِمَّا يَشَآءُ ۗ وَلَوْلَا دَفْعُ ٱللَّهِ ٱلنَّاسَ بَعْضَهُم بِبَعْضٍ لَّفَسَدَتِ ٱلْأَرْضُ وَلَـٰكِنَّ ٱللَّهَ ذُو فَضْلٍ عَلَى ٱلْعَـٰلَمِينَ
So they defeated them by permission of Allah, and David killed Goliath, and Allah gave him the kingship and prophethood and taught him from that which He willed. And if it were not for Allah checking [some] people by means of others, the earth would have been corrupted, but Allah is full of bounty to the worlds.