So in the very first pages of this book, Rahner states essentially that one of the challenges of his book is people approaching it who are not smart well-read enough will find it very challenging and might dismiss it out of hand. I am that person, though I tried to work with it and meet the text where it was at. 

Needless to say, I would have gotten way more out of this book if I had a stronger grounding in like very basic theology and philosophy. This isn't to say it was wholly worthless to me--some sections I found super enlightening and powerful, especially the section on the church, and there are specific parts I would love for everyone to read to better understand how Catholicism works and functions as a religion, as a body composed of a church and of individuals. More challenging sections that I would probably need to return to a couple of times include the chapter on Jesus Christ (yes, hilarious that is the chapter I didn't understand the most in a book about Christianity,) and the one about eschatology. 

Still probably the most comprehensive book about Catholic theology I've ever read, and despite some of the challenges in terms of density, I would say Rahner's writing is very approachable, and even funny at times. (His section about the use of the word God in particular had me giggling.) Would say definitely a necessary read and I hope I can some day come back to this with a better appreciation for the nuances and a better understanding overall.