Since Dr. Lee's book Keys to Studying Well came out in November, 2011, the book has won over the hearts of non-Christians as well as Christians. It is now being called by the nickname "Today's Christian Book" or "Best Christian Book" in the major bookstores of Korea. The book suggests the effective methods to study by controlling our spirit, soul and body.

Other books by Dr. Lee such as The Message of the Cross, Heaven I & II, Hell, and Tasting Eternal Life before Death are available in well-known major book stores. Spirit, Soul, and Body I was on the bestseller list for seven month in a row.