Rambam's Sea

In the last law of the Mishne Torah the Rambam writes that in the time of Moshiach the world will be filled with the knowledge of G-d as the waters cover the sea beds.  The analogy is teaching us that the sea, which is full of all kinds of creatures and hidden things, is completely immersed and unnoticeable under the waters. The same way soon when Moshiach comes, the whole world and everything in it will exist, but it will be unnoticeable compared to the knowledge of G-d which we will all posses.

After this we go back to the beginning of the Mishne Torah and read the first halachah which stated: the the beginning of all beginnings and the cause of all causes is G-d, so our knowledge is heightened and we realize that there is nothing besides G-d.