Vast seas, which are the perfect work of Allah, make one think when they look at it.
Water covers three-thirds of Earth’s surface entire. Because of this, neither can the freezing colds of the North and South Poles nor the scorching tropical heat can take Earth in their grip. The Earth’s surface, warmed up by the rays of the Sun during the day, distributes this heat all around, like a radiator. As for the seas, despite receiving millions of calories of heat from the Sun, they can warm up only to a certain degree; but once warmed up they do not lose their heat easily. So, the Earth’s seas regulate climates and act as a thermostat moderating against excessive heat or cold; hence the reason why they are of greater mass compared to land. By virtue of vaporization, they moreover satisfy the need lands stand in for water. Lesser seas would have meant lesser vaporization and that would have resulted in a drought fierce enough to turn the entire land on Earth to desert.
No less are the characteristics of maritime beings to those of land. Pearls, corals and other adornments and especially the fresh seafood acquired from the depths of seas are of particular importance to human beings.
The survival of all beings on Earth depends on water. A person, unable to find water despite desperately needing to, would doubtless not blink an eye in surrendering all the treasures of Earth just to have one precious sip. Again, he would not think twice about relinquishing all of Earth’s treasures just to release the consumed water from his body, if he was unable to. Man is cause for wonder! Just how does he make such a big deal of gold and silver while remaining oblivious to the enormity of the blessings placed by the Almighty within just a single sip of water?
It would not take long for a person, who contemplates these underlying wisdoms as is worthy of their nature, to realize that all beings on Earth depend on the protection and aid of a Creator of infinite knowledge and power just to survive. He would come to terms with the fact that he lives under miraculously perfect conditions, in a virtual wonderland, he herself would have been unable to maintain. Neither reason nor conscience would then be blind enough to have the nerve to rebel against Allah, glory unto Him, the Creator and the Regulator of the Universe.
 See, Imam Ghazzali, Ihyâ, VI, 65-66.
Source: Osman Nuri Topbaş, Contemplation in Islam, Erkam Public.