Vocabulary enables us to interpret and to express. If you have a limited vocabulary, you will also have a limited vision and a limited future. - Jim Rohn
Darkness limits our freedom because it prevents us from moving around quickly. Consequently light gives us freedom because it allows us to see the world around us more clearly.
Language is like a light bulb burning in the darkness of ignorance. The limits of our vocabulary are the limits of our communication and thoughts. So you could say that the greater our mastery of language is, the brighter the bulb. And the brighter the bulb, the further we can see.
The world around us is dark enough already, why should we choose to make it darker by not expanding our horizons to at least the limits of known and set by other men?
The limits of my language mean the limits of my world -Ludwig Wittgenstein