Surah Al-An'am 6:35

وَإِن كَانَ كَبُرَ عَلَيْكَ إِعْرَاضُهُمْ فَإِنِ ٱسْتَطَعْتَ أَن تَبْتَغِىَ نَفَقًا فِى ٱلْأَرْضِ أَوْ سُلَّمًا فِى ٱلسَّمَآءِ فَتَأْتِيَهُم بِـَٔايَةٍ ۚ وَلَوْ شَآءَ ٱللَّهُ لَجَمَعَهُمْ عَلَى ٱلْهُدَىٰ ۚ فَلَا تَكُونَنَّ مِنَ ٱلْجَـٰهِلِينَ

And if their evasion is difficult for you, then if you are able to seek a tunnel into the earth or a stairway into the sky to bring them a sign, [then do so]. But if Allāh had willed, He would have united them upon guidance. So never be of the ignorant.

Translation: Saheeh International

Tafsir

And if their aversion to Islam is grievous too great for you on account of your concern for them then if you can seek out a hole an underground passage in the earth or a ladder a stairway to heaven that you may bring them a sign from among those they have requested then go ahead the meaning is that you will not be …

Excerpt from Tafsir al-Jalalayn, commentary on 6:35, via Quran.com. The reader has the full commentary and 9 more tafsirs.