وَمَا كَانَ النَّاسُ إِلاَّ أُمَّةً وَاحِدَةً فَاخْتَلَفُواْ وَلَوْلاَ كَلِمَةٌ سَبَقَتْ مِن رَّبِّكَ لَقُضِيَ بَيْنَهُمْ فِيمَا فِيهِ يَخْتَلِفُونَ
[10:19]
And people are naught but a single nation, so they disagree; and had not a word already gone forth from your Lord, the matter would have certainly been decided between them in respect of that concerning which they disagree.
Mankind was but one nation, but differed (later). Had it not been for a word that went forth before from thy Lord, their differences would have been settled between them.
Mankind were but one community; then they differed; and had it not been for a word that had already gone forth from thy Lord it had been judged between them in respect of that wherein they differ.