Surah Al-A'raf — Ayah 203 (7:203)
وَإِذَا لَمۡ تَأۡتِهِم بِـَٔايَةٖ قَالُواْ لَوۡلَا ٱجۡتَبَيۡتَهَاۚ قُلۡ إِنَّمَآ أَتَّبِعُ مَا يُوحَىٰٓ إِلَيَّ مِن رَّبِّيۚ هَٰذَا بَصَآئِرُ مِن رَّبِّكُمۡ وَهُدٗى وَرَحۡمَةٞ لِّقَوۡمٖ يُؤۡمِنُونَ ٢٠٣
English translation (Saheeh International)
And when you, [O Muḥammad], do not bring them a sign [i.e., miracle], they say, "Why have you not contrived it?" Say, "I only follow what is revealed to me from my Lord. This [Qur’ān] is enlightenment from your Lord and guidance and mercy for a people who believe."
Brief commentary
And If you O Messenger come with a sign, they reject it and turn away from it; and if you do not come to them with a sign, they ask why he did not produce one. Say to them O Messenger: 'It is not up to me to just come with a sign. Rather, I only follow what was revealed to me from Allah: the Qur’ān which I recite to you, an evidence and proof from Allah your Creator, the arranger of your lives, a guidance and mercy for the believers among His creation. As for those who do not have faith, then they are lost and wretched.'