Vital Ruby concepts to learn before I jump into Rails? -

Disclaimer - Ruby is the first language I've ever learned, I do not have a CS background.

I have worked through Chris Pine's "Program to Learn to Program" which has been pleasant and now I understand the basics very well. The next recommended book will be "Programming Ruby 1.9" (Next Pickex). What I have read is only a huge reference book, but it is 960 pages and it scares me.

In your opinion, the next 'what-know' concepts should be learned which I should learn? / P>

Thanks in advance.