Surah Al-Anfal, ayah 43

8:43

إِذۡ يُرِيكَهُمُ ٱللَّهُ فِي مَنَامِكَ قَلِيلٗاۖ وَلَوۡ أَرَىٰكَهُمۡ كَثِيرٗا لَّفَشِلۡتُمۡ وَلَتَنَٰزَعۡتُمۡ فِي ٱلۡأَمۡرِ وَلَٰكِنَّ ٱللَّهَ سَلَّمَۚ إِنَّهُۥ عَلِيمُۢ بِذَاتِ ٱلصُّدُورِ ٤٣

Idh yurīkahumullāhu fī manāmika qalīlan walaw arākahum kathīral lafashiltum walatanāza'tum fil-amri walākinnallāha sallama innahū 'alīmu bidhātis-sudūr

[Remember, O Muḥammad], when Allāh showed them to you in your dream as few; and if He had shown them to you as many, you [believers] would have lost courage and would have disputed in the matter [of whether to fight], but Allāh saved [you from that]. Indeed, He is Knowing of that within the breasts.