As nothing is created in vain, so are the blessings of Allah. Any of these blessings; our life, faith, sustenance, health, eyes, ears and all are reasons for mankind to be grateful to Allah.
When one leaves the heedless and ignorant vision and starts to think and see with reasoning, he will surely ascertain that everything around us is indeed a favor of Allah. All the food that we eat, the air that we breathe, all the beauties around us, also our eyes that let us see all these, everything but everything is a blessing of Allah. These are so numerous that the Qur'an informs: " if ye would count up the favours of Allah, never would ye be able to number them: for Allah is oft-forgiving, most merciful." (an-nahl,18)
and undoubtedly all these favors are given for some reason. Nothing is created for us to use as we wish and consume. On the contrary, the reason of all those favors -no matter what - is to instruct mankind towards Allah; because everything given, necessitates a gratitude in return. Allah is the one who continuously gives all the blessings; we should show our sincere gratitude only to him. Gratefulness is both a great prayer and also a way to protect us from "transgressing". Because people have a tendency towards depravity and evil as they get richer and have more power. They start to forget their weaknesses and become haughty. Showing our gratitude to Allah prevents us from this "depravity". people who show their gratefulness to Allah know that everything they obtain is given to him by Allah, to whom they always belong to. That's why we are responsible for using these blessings in the way of Allah and for only his will. This is the key for modesty and maturity of the prophets such as davud (David) or suleyman (Solomon) to whom great possession, states and sovereignty are given. The actual problem of karun (qarun), who was depraved because of the possession he had, was indeed being ungrateful to Allah.
if a believer demonstrates that he will not become haughty and impertinent with the blessings or riches he is given, Allah shall give him more. "...if ye are grateful, I will add more (favours) unto you; but if ye show ingratitude, truly my punishment is terrible indeed." (ibrahim 7)
Gratitude should not be shown merely with words; it should instead be mostly shown by utilizing each favor for Allah's way. Believers are responsible of using everything that they have been given, for the way of Allah. First of all, all the believers should start using their being to strive for his way. Qur'an also informs that to show our gratitude to Allah can be done by proclaiming people about all of Allah's blessings, which is telling them about the belief of Allah:
"and soon will thy guardian-lord give thee (that wherewith) thou shalt be well-pleased. Did he not find thee an orphan and give thee shelter (and care)? And he found thee wandering, and he gave thee guidance. And he found thee in need, and made thee independent. Therefore, treat not the orphan with harshness, nor repulse the petitioner (unheard); but the bounty of the lord - rehearse and proclaim!"
Moral Values Of The Qur'an; By Harun Yahya