Q:

Please anyone explain what is the difference between English and The English language?

Between the three sentences

English opens the the window upon the world's knowledge.
English language opens the the window upon the world's knowledge.
The English language opens the the window upon the world's knowledge.

I think first one is more appropriate but can the remaining two sentences imply same meaning?
If not what is their meaning?
Are they grammatically correct? Please explain to me.

A:

One meaning of the word English is the English language. (See Cambridge dictionary). So Sentences 1 and 3 mean the same thing and they are both appropriate. 
Sentence 2 is not good because of the lack of a determiner before English language. When it is used as a noun, English language needs an article (or some kind of other determiner, such as a number: One English language is all the world really needs). Most of the time the article will be the because English language, like Engish by itself, is a proper noun.
However, sometimes proper nouns can be used with the indefinite article: American English is an English language that I don't like. I prefer New Zealand English. Now that's an English language I can get excited about. 

