Surah Al-Kahf (The Cave), Verse 14

وَّرَبَطْنَا عَلٰی قُلُوْبِهِمْ اِذْ قَامُوْا فَقَالُوْا رَبُّنَا رَبُّ السَّمٰوٰتِ وَالْاَرْضِ لَنْ نَّدْعُوَاۡ مِنْ دُوْنِهٖۤ اِلٰهًا لَّقَدْ قُلْنَاۤ اِذًا شَطَطًا ۟

Wa rabatnaa 'alaa quloo bihim iz qaamoo faqaaloo Rabbunaa Rabbus samaawaati wal ardi lan nad'uwa min dooniheee ilaahal laqad qulnaaa izan shatataa

“We gave strength to their hearts: Behold, they stood up and said: "Our Lord is the Lord of the heavens and of the earth: never shall we call upon any god other than Him: if we did, we should indeed have uttered an enormity!”

Quran 18:14 (Yusuf Ali Translation)