Surah Ar-Ra'd — Ayah 27 (13:27)
وَيَقُولُ ٱلَّذِينَ كَفَرُواْ لَوۡلَآ أُنزِلَ عَلَيۡهِ ءَايَةٞ مِّن رَّبِّهِۦۚ قُلۡ إِنَّ ٱللَّهَ يُضِلُّ مَن يَشَآءُ وَيَهۡدِيٓ إِلَيۡهِ مَنۡ أَنَابَ ٢٧
English translation (Saheeh International)
And those who disbelieved say, "Why has a sign not been sent down to him from his Lord?" Say, [O Muḥammad], "Indeed, Allāh leaves astray whom He wills and guides to Himself whoever turns back [to Him] -
Brief commentary
Those who disbelieved in Allah and His verses say: If only a physical sign was sent down to Muhammad from his Lord proving his truthfulness and then we will believe. Say, O Messenger, to those who suggest this: Allah, through His justice, leaves whoever He will to stray, and through His grace He guides to Himself those who turn towards Him in repentance. Guidance is not in their hands so that they could link it to the sending down of signs.