What is the connection between literature and grammar?

Literature is a vast study of the many authors of our times, their poetry, novels, and other works. We study English literature and also works from people from all over the globe. Keeping in mind that their 'grammar' is reflective of their times, seasons, decades and centuries. We know that grammar has changed throughout the years and that when speaking, we use Standard English in professional atmospheres and in schools. As teachers, we teach our students to correctly use standard english, all the while watching a nation of young people butcher Words with their own versions of text-talk, slang, idioms, etc. These are the challenges of teachers to cross reference studying the language of literature and balancing it with engilsh grammar.

No matter, we need to understand where our Words come from (Latin, Greek) and that everyday as our cultures cross one another, we gain even more Words and language from others. We continue to borrow Words from others and use them in our daily language.

The connection I see is when reading something by Robert Frost, I know that there will be language and grammar unfamiliar (whereunto, hence, etc.) or Shakespeare, (whereforth art thou) and that grammar does still continue to play a huge part in our reading, speaking, studying and writing.