Respect every thing you have now!

You should respect each and every thing you have now because one day you will wake up and realize the value of those things which you have lost. 
The man having bike will see the man with car and wish if he had a car. The man having cycle will look at the man with bike and wish if he had a bike. Similarly , the man walking in the road will see the man with cycle and wish if he had a cycle. And , the man who is disabled and cannot walk around will see the man walking and wish if he could walk and go wherever he want. 

So, instead of thinking about what you do not have , you should see and realize what you have and know the value of those things because in order to live happy and prosperous life  you should be satisfied with your life.