It has become a common Christian refrain from our carved out subculture - "It doesn't matter if you know everything about God if you don't know God." Fair enough. The problem is that first, I've never met anyone who knows everything about God, and second, I know a lot of people who know Him, but don't know much at all about Him. Sometimes it's ok to say, "I need to learn more about the God I serve, and the world He created."
Almost ten years ago I became fascinated with Christian apologetics. I wanted to learn as much as I could as quickly as possible. In three months I went from knowing very little to being confident about teaching a class on the subject. The method I discovered can be used by anyone and with other categories than apologetics. I encourage all believers who desire to grow in knowledge to give it a try.
1. LISTEN TO PODCASTS - Unless someone is with me I'm listening to some kind of educational audio almost all the time. This was a difficult switch because I love music. Even now, occasionally a new album will come out and I'll take a break for a few days, but for the most part if you see me driving I'm learning. The same goes for the gym. From the moment I put on the earbuds and leave the locker room I'm listening to something. If you're into apologetics, my list includes The Reasonable Faith podcast, the Defenders Class (with William Lane Craig), The Don Johnson Radio Show, Unbelievable (with Justin Brierley), Theology Matters (with the Pellews), Deeper Waters (with Nick Peters), The Dividing Line (with James White - careful with this one) and of course, The Trinity Crusades Radio Program (with me and Johnathan Pritchett). To expedite apologetics learning, listen to debates. Listen to a ton of debates. This way you get to hear the defense and the critique.
For a host of free resources check out apologetics315.com
If your not into apologetics (even though you should be) and you'd rather here sermons, check out Let My People Think (with Ravi Zacharias) or just pick any well known pastor. He's probably got a podcast. And if your a pastor, and thus are expected to know everything about everything, you might enjoy Stuff You Should Know, Stuff You Missed in History Class and Freakonomics Radio.
For a host of free seminary style lectures check out biblicaltraining.org.
2. LISTEN TO EBOOKS ON YOUR PHONE - It's the 21st century and while you might be one of those, "I like to smell the pages" kind of people, the point is learning and you can learn a lot faster with modern technology. Most ebook software has a function to read out loud to you. You can even set it to double or triple speed (this is also true of podcasts). The faster speeds you have to work up to and the computerized artificial voice is annoying at first, but you'll get there.
3. USE ITUNES U AND YOUTUBE - Believe it or not Apple has made thousands of full courses from every imaginable institution of higher learning available for free. You can even get the study guides. Some of them are video related and some are just audio, but when I discovered this I got noticeably giddy. As far as Youtube is concerned, you have to be careful. Nevertheless, the site is good for everything from learning how to do laundry to understanding the cosmological argument for God's existence so don't discount it too quickly.
4. TALK TO OTHERS ABOUT WHAT YOU'RE LEARNING - Do not skip this step! You need a learning buddy. It's best if you share enough interests in common with someone that you can talk about what you're learning together. However, any friend who is a good listener will do. Unless you have the greatest marriage in history, don't use your spouse. He/she does not want dinner time to become a seminary lecture. Don't do it. Seriously. Don't.
I was fortunate enough that when I was first getting into apologetics my friend Andy was at about the same level of understanding. We read different books and then shared our insights with each other. This saved time by doubling the speed at which we were learning.
5. PRAY - You will do none of this if you aren't passionate about the process. I recommend asking God to give you a passion for learning. He did for me. Then praise Him for the truths that you are learning.