Surah Al-Kahf (The Cave), Verse 56

وَمَا نُرْسِلُ الْمُرْسَلِیْنَ اِلَّا مُبَشِّرِیْنَ وَمُنْذِرِیْنَ وَیُجَادِلُ الَّذِیْنَ كَفَرُوْا بِالْبَاطِلِ لِیُدْحِضُوْا بِهِ الْحَقَّ وَاتَّخَذُوْۤا اٰیٰتِیْ وَمَاۤ اُنْذِرُوْا هُزُوًا ۟

Wa maa nursilul mursaleena illaa mubashshireena wa munzireen; wa yujaadilul lazeena kafaroo bilbaatili liyudhidoo bihil haqqa wattakhazooo Aayaatee wa maaa unziroo huzuwaa

“We only send the messengers to give Glad Tidings and to give warnings: But the unbelievers dispute with vain argument, in order therewith to weaken the truth, and they treat My Signs as a jest, as also the fact that they are warned!”

Quran 18:56 (Yusuf Ali Translation)