وَأَلْقَى فِي الْأَرْضِ رَوَاسِيَ أَن تَمِيدَ بِكُمْ وَأَنْهَارًا وَسُبُلًا لَّعَلَّكُمْ تَهْتَدُونَ
He cast firm mountains in the earth lest it should shake with you, and [made] streams and ways, so that you may be guided
Agha Ali Puya Commentary
Commentary on Quran 16:15
[Pooya/Ali Commentary 16:15] Aqa Mahdi Puya says: Refer to Ar Rad: 3 and Al Hijr: 19. It is a figure of speech, repeatedly used in the Quran, to speak of the earth as a stretched surface with mountains as a steadying agent to keep it from shaking. It may refer to the geological fact that the below the surface happenings would have shaken the earth if there were no mountains to keep it steady. Imam Ali said: "Allah has steadied the movement of the earth by bolting rocks in it." "Allah bolted the earth with rocks to keep it from shaking."