Frost – The figure a poem makes

Like a piece of ice on a hot stove the poem must ride on its own melting. A poem may be worked over once it is in being, but may not be worried into being. Its most precious quality will remain its having run itself and carried away the poet with it. Read it a hundred times: it will forever keep its freshness as a metal keeps its fragrance. It can never lose its sense of a meaning that once unfolded by surprise as it went.

Rilke – Letters to a young poet

…. save yourself from these general themes and seek those which your own everyday life offers you; describe your sorrows and desires, passing thoughts and the belief in some sort of beauty – describe all these with loving, quiet, humble sincerity, and use, to express yourself, the things in your environment, the images from your dreams, and of your memory.