My answer was (as closely as I can recall):
As long as I read properly, that is, not reading just for the sake of getting through them as to gain knowledge in order to boast (unfortunately, this still happens to me as I am still a sinful man), but read them "prayerfully" then yes, reading definitely helps.
I used the word "prayerfully" with much nuance so to include the meanings of other related words like, "meditatively", "worshipfully", "humbly", "God-centred", etc.
Well, provided you do read books "prayerfully", I think Colin gave a fine list of reasons for reading.
Colin qualifies it by saying these words before though:
A couple of qualifications before I get started. Firstly, I remain convinced that reading Scripture is primary. Let me also add that I’m mainly talking about Christian books and most certainly good Christian books.
I agree with the first one, reading the Bible must be primary for all Christians. But with the second one, well, I would say it is helpful and good to read almost any book, not only limited to good Christian books as long as you read them "prayerfully". Actually, I'd be happier to read a secular book than to read a "bad Christian book", eg. prosperity-Gospel-like books, books claiming to be touching a serious topic yet fails to be more than a superficial or lazy attempt, a book that is (or a book by an author who is) lacking in integrity, and so on.
(HT: Justin Taylor)