The Holy Prophet has told us to appreciate five things before they go, one of which is youth before old age. Youth possess phenomenal amount of energy, and if this energy is channelled in the correct way it can guarantee a place in Paradise.
A person is physically and mentally the most active when they are young. It is during this stage in life that they can greatly benefit society around them. The great Mohammad Bin Qasim-Al-Thaqafi, a 19 year-old Arab general from Basra (Iraq) marched into Pakistan by way of Persia and Balochistan with an army of 60,000 men.