Quran At-Tur 52:38
أَمۡ لَهُمۡ سُلَّمٞ يَسۡتَمِعُونَ فِيهِۖ فَلۡيَأۡتِ مُسۡتَمِعُهُم بِسُلۡطَٰنٖ مُّبِينٍ ٣٨
Translation
Or have they a stairway [into the heaven] upon which they listen? Then let their listener produce a clear authority [i.e., proof].