The texture and the nature of the hands and feet are different from the eyes and the inner part of the ear. For instance, the eye will not tolerate a little dust particle to enter it, whereas the feet will walk comfortably over heaps of sand. Further, consider the hand. Its use is as far as it can stretch. It cannot reach beyond that and take hold of anything. The ear though can pick up sounds from a distance much further away. As for the eyes it can see and reach as far as the moon and the stars. These limbs have different levels of perception and strength. However, stronger than all of these is the mind. Within seconds it can travel the entire world without the body moving an inch. It can rule empires and it can invent the latest in technology. But despite of all this, the mind is controlled by the heart, and the heart is either going to be serving one Allah or else it will be the slave of the material world. Intelligence demands that we hand over ourselves to one Allah and the world will continue to serve us.