It appears you don't understand something. When most people don't understand something they will attribute it to god. Therefore language would be a god given gift. (no other explanation required)
Sadly, but as you are trying to understand and explore it further & rationally there is much complexity to what you ask, which includes, evolution, history, biology, neurology, psychology etc...
We have developed language which enables us to communicate & to express ourselves. This is the part what answers your question the best.
For example you want to communicate you want to understand something, so you ask the question above. In order to gain you have to arrange words - (the motivation for this action is you requiring an answer, therefore weather you're aware of it or not, this is the process that is happening) - you want something and you do what you can to get it, if you can speak, this is the easier route. People without speach may bang and point or draw. Speaking or writing language is an automatic process like driving or walking, we don't think we need to put one foot in front of the other to walk, we just do it, like with words, they too get us from one place to another.