Surah Al-Anam, verse 19

قُلْ أَىُّ شَىْءٍ أَكْبَرُ شَهَـٰدَةً ۖ قُلِ ٱللَّهُ ۖ شَهِيدٌۢ بَيْنِى وَبَيْنَكُمْ ۚ وَأُوحِىَ إِلَىَّ هَـٰذَا ٱلْقُرْءَانُ لِأُنذِرَكُم بِهِۦ وَمَنۢ بَلَغَ ۚ أَئِنَّكُمْ لَتَشْهَدُونَ أَنَّ مَعَ ٱللَّهِ ءَالِهَةً أُخْرَىٰ ۚ قُل لَّآ أَشْهَدُ ۚ قُلْ إِنَّمَا هُوَ إِلَـٰهٌ وَٰحِدٌ وَإِنَّنِى بَرِىٓءٌ مِّمَّا تُشْرِكُونَ ﴿١٩﴾

6:19 Say, “Whose testimony is the greatest?” Say, “Allah is Witness between me and you. This Qur’an has been revealed to me so that I may warn you thereby and whomsoever it reaches. Do you really bear witness that there are other gods besides Allah?” Say, “I do not bear such witness.” Say, “Indeed, He is One God, and I disown all that you associate [with Him].”