John describes three stages of spiritual growth in God's family:

1) Fathers, the most mature spiritually and knowledge.

2) Young men, not yet spiritually mature, but do know sound doctrine.  They are strong against sin.  

3) Little children, have only the basic awareness of God and need to grow.

All that is in the world is based upon the lusts of the flesh, the lusts of the eyes, and the pride of life.  These are objects sought by the people of the world; these are not objects to be sought by the Christian.  It is not the nature of true religion to seek these things.  The sincere Christian has nobler ends.  

The lusts are so much the object of desire, which will eventually disappear forever.  But he that doeth the will of God has built his happiness on a basis which is secure, and which abideth forever.