La vie est une fleur. L'amour en est le miel. – Victor Hugo
It's translated as “Life is a flower. Love is the honey.”
But what does en mean there? Why isn't it translated?
It could be more clearly translated to
In the translation you provided, this relation could be implicitly understood
En together with y are adverbial pronouns. They both replace an antécédent, i.e. a complement previously mentioned in the context.
Also, because French's indefinite articles for uncountables or undetermined plurals are built on a genitive / ablative, you will find:
What is more, it can be used with the undetermined article un or rather with cardinal determiners like un, deux, trois, etc. In which case you have to understand the implicit genitive il a pris une pomme (indéterminée parmis les pommes qui existent).
Be careful! en and y always come last in a series of pronouns.