Kur’an 18:97 — sura Al-Kahf, 97. ajet

فَمَا ٱسۡطَٰعُوٓاْ أَن يَظۡهَرُوهُ وَمَا ٱسۡتَطَٰعُواْ لَهُۥ نَقۡبٗا

I tako oni nisu mogli ni da ga pređu niti su ga mogli prokopati.

So Gog and Magog were unable to pass over it, nor were they able [to effect] in it any penetration