Al-Anbiya' - 21:65

ثُمَّ نُكِسُوا عَلَى رُؤُوسِهِمْ لَقَدْ عَلِمْتَ مَا هَؤُلَاء يَنطِقُونَ
[21:65]
Then they were made to hang down their heads: Certainly you know that they do not speak.
Then were they confounded with shame: (they said), "Thou knowest full well that these (idols) do not speak!"
And they were utterly confounded, and they said: Well thou knowest that these speak not.