Imam ‘Ali (a.s.) said:
وَ وَتَّدَ بِالصُّخُورِ مَيَدانَ اَرْضِهِ
Shaking and movement of the Earth is prevented by mountains.1
Nowadays, it has been confirmed that just as the gravity of the moon effects the ebb and flow of seas (producing high tides twice a day, raising the water level one meter or more and even 15 meters in some parts) it also causes up and down movement of 30 centimeters in the solid crust of the earth.
But solidity of earth’s crust due to existence of mountains, the roots of which are connected to each other creating a stabilizing network round the earth, prevents any noticeable movement.
Just imagine ! If there were no mountains and earth’s crust was not solid, and in a state of continual flux and reflux, what would happen to our quiet and peace on this earth?
This is just another example of Islamic leaders mentioning scientific facts 14 centuries ago which science has discovered much later.