Is there such a State as Eternal Life?

Is the idea of living forever in a happy state just wishful thinking or do we have some basis for believing that eternal life can be a reality?  People have many opinions and beliefs about death and the after life.  But God tells us in His Word that eternal life is a reality and He tells us how we can get eternal life.  John 3:15 says, “That whosoever believeth in him (Jesus) should not perish, but have eternal life.”