When I Have Fears that I May Cease to Be

This is a very complex poem. It has a lot of meanings hidden on it. One things I thought it was magnificently written by John Keats was the idea of being afraid to die before writing all the things his head needed to. This is brilliant because it represents the idea that one of the most important things in life is writing, and that it must be accomplished above all things. Another thing that is beautiful from this poem is how this man claims he is also afraid of not seeing his beloved again.
One of the most important phrases from the poem is:
... then on the shore 
Of the wide world I stand alone, and think 
Till Love and Fame to nothingness do sink.
Because it also represents how the time is fading, it represents the time spent.