"And We placed within the earth firmly set mountains," meaning: the mountains, "lest it should shake with them," so that it would not move with them; "and We made therein broad paths as ways," meaning: landmarks and roads, "that they might be guided," so that they may be guided to the paths.
﴿وَجَعَلنَا فِي الأَرْض رواسي﴾ يَعْنِي: الْجِبَالَ ﴿أَنْ تَمِيدَ بِهِمْ﴾ لِئَلَّا تَحَرَّكَ بِهِمْ ﴿وَجَعَلْنَا فِيهَا فجاجا سبلا﴾ يَعْنِي: أَعْلَامًا طَرِقًا ﴿لَعَلَّهُمْ يَهْتَدُونَ﴾ لكَي يهتدوا الطّرق