They asked: Ya Ali;.
What is God's most powerful creation?!
He said: Mountain!
But the iron rules it,.
Iron is also defeated by fire.
Fire is also defeated by water.
The water itself, defeated by the wind,.
Man also controls the spirit.
and tame him;.
Therefore, it is stronger than the wind.
but;.
Man himself is defeated by sadness!
so sad; He is the most powerful creation of God... - Al-Gharat, Vol. 1, p. 182.