SICP contains nothing about Homoiconicity

Check the index!

Now I am a beginner and I except an introductory computer science book to mention such an abstract ``wordy'' subject.

It's correlated in a threshold way. There's a threshold IQ level below which it may be said certainly that that person is a dumbass. But having a high IQ doesn't say anything about the intelligence besides "he's not a dumbass". A high IQ score doesn't say anything about knowledge, education, about expertise, about analytical skills or cognitive abilities. It just means that the person's not braindead and is good at basic logic and pattern matching.