Fulness

There are certain phrases and expressions used at church that are confusing and, I am beginning to think, misused.  I am on a journey to understand what is actually meant by these expressions.  I wanted to share an insight I had about the phrase "fulness of the Gospel".  The Doctrine and Covenants says that the Book of Mormon contains the "fulness of the Gospel".  I think when people speak of this reference they speak as if the Gospel in its completeness is in the Book of Mormon.  Is that true?  Why do we have other scriptures?  Why do we have additional revelation?   What does fulness actually mean?  It means enough to be content and not want more.  When I am full from eating, I have not consumed every possible piece of food in the world, or even all the food at my disposal.  When my car's tank is full, there is still a lot of gas that is not in my tank.  My tank has reached its capacity.  So maybe saying we have the fulness of the Gospel just means that we have enough to be satisfied for now, but possibly there is much more to have.  And perhaps we should be a little less satisfied and a little hungrier for more.