All of this is designed to help you filter the few books you will read from the thousands you could read. Not only that, but it is designed to help you get a sense of what a book is all about before you begin to read it. When you are quite new to Christian books, there is value in choosing your books carefully to avoid bad influences.
They are far and away the most common questions I receive (beyond, perhaps, how to pronounce my name—it rhymes with “valleys”): Can you tell me anything about this author? Have you heard of this book? Is it safe to read? Sometimes people ask to avoid wasting time or money on a book that would not be worth either one, and sometimes they ask to avoid the influence of false doctrine. Since I can’t answer all the questions, and since I can’t know all the books and authors, I’ll offer a few tips on sorting it all out and do so in the form of 5 questions you can ask of any book.
Who wrote you? Familiarize yourself with trustworthy authors. As a reader you should have your list of favorites, the short list of people you regard as especially influential and trustworthy. I believe there is a lot of value in tracking a few authors through the course of their career and reading—or at least considering—every one of their books. This is difficult with an R.C.Sproul since if you begin today you are 100 books behind, but much easier with younger authors who have a shorter list of works. Don’t know where to begin? Then ask a friend or pastor. Or ask me. I’d try people like H.B.Charles Jr., Kevin DeYoung, Gloria Furman, Russell Moore, Andy Naselli, Barnabas Piper, or Jen Wilkin—people like that. They have each written a few books but not so many that you’ll need to spend two years catching up, and they are all likely to write quite a few more. Find “your” authors and read what they write. But then also track who endorses their books, who speaks at conferences with them, and so on. Start to look for connections.
Who published you? You should familiarize yourself with Christian publishers and learn which of them are especially trustworthy. There are quite a lot of excellent publishers whose books may vary by quality and secondary theological issues but which will never fall outside the conservative Evangelical stream. Learn to trust these ones. Among them are Banner of Truth, Christian Focus, Crossway, Evangelical Press, Matthias Media, P&R, Reformation Heritage, Reformation Trust, The Good Book Company, (and, I hope, Cruciform Press since I was involved in founding it). If they publish it, you can be quite confident in it. Other publishers publish a much wider range of titles and, depending on the company, the imprint, or the department, their titles may range from very good to quite concerning or from very good to outright heretical. For these you will need to exercise a bit more caution. Here I refer to IVP, Eerdmans, Multnomah, Thomas Nelson, Zondervan, as well as the faith or Christian imprints of large mainstream publishers (Harper Collins, Penguin, and so on).