﴿ ثُمَّ نُكِسُوا۟ عَلَىٰ رُءُوسِهِمْ لَقَدْ عَلِمْتَ مَا هَٰٓؤُلَآءِ يَنطِقُونَ ﴾

“But then they relapsed into their former way of thinking and said: “Thou knowest very well that these [idols] cannot speak!””

Please check ayah 21:67 for complete tafsir.