Read books by people you don’t entirely agree with. Listen to their arguments in their own words. By doing this you will see their arguments presented in their most believable form. If you are only familiar with the arguments of others as they are presented to you by your own teachers, you might only be familiar with watered-down or straw men representations of someone else’s position. Who knows? Maybe you are actually wrong about something every now and then? Don’t be afraid of truth. Don’t be afraid to be mistaken. If we’re wrong, we want to know it. If we’re right, we want to know how to explain our opponent’s error in the most powerful way possible. We can only do this by wrestling with their arguments presented in their most strongest form.
We should also make a habit of reading books by people we do agree with, but we should read those books just as (if not more) critically. There is obvious benefit to understanding our own positions better. But even the best uninspired books are uninspired. It is good to learn from good people. But even good people make mistakes. Don’t let your guard down just because you trust a particular author.
Most books don’t fit neatly into a categories of “books I agree with” and “books I don’t agree with.” Most books will be mixed bags. If you develop the habit of reading books critically, you will find that you can learn things from almost anybody, but at the same time, it will be very rare that you find yourself agreeing with anybody entirely. “Chew up the meat and spit out the bones” is good advice.
Finally, as you develop the habit of reading books, remember to read the Bible more. Reading books written by men is very beneficial, but nothing is as important as filling your mind with Scripture. Reading uninspired books can give you new things to think about as your read Scripture, and continually filling your mind with Scripture helps you to think critically about the other books you read. Read books, read them critically, and read Scripture even more.