Surah An-Nur, ayah 16

وَلَوۡلَآ إِذۡ سَمِعۡتُمُوهُ قُلۡتُم مَّا يَكُونُ لَنَآ أَن نَّتَكَلَّمَ بِهَٰذَا سُبۡحَٰنَكَ هَٰذَا بُهۡتَٰنٌ عَظِيمٞ ١٦

Walawlā idh sami'tumūhu qultum mā yakūnu lanā an natakallama bihādhā subhānaka hādhā buhtānun 'azīm

And why, when you heard it, did you not say, "It is not for us to speak of this. Exalted are You, [O Allāh]; this is a great slander"?