...so what's our biggest problems?

Think about this before you reply. Really think it through.

What thing (activity, mindset, etc) is crippling us as Christians? There are lots of things, obviously. "We don't love others enough." Check. "We don't look or act any different than the world." Double-Check. But what are some of the more subtle things that makes an entrance in the body of Christ that breaks us down rather than strengthens us?

For example;
One of our weak points, in my opinion, is definitely this one;
"Love the Lord your God with all your heart, soul, mind, and strength."

I think all too often we focus on the 1st, 2nd, and 4th, quickly disregarding the 3rd. I personally love learning, so others may think this is easy for me to say. Christians are often seen as having a touchy-feely, lofty faith (watch Oprah for an example of this) instead of one that is logically and factually sound. Science, for example, is on our side. But most of us don't know it.
And if we do know it, we sure don't spend time learning how it is on our side. We don't spend time learning from Peter when he tells us to be ready to give a defence for your faith. All we know is that Christ gives us comfort and joy- beyond that, it's up to the theologians. We should spend time studying the word, building up our minds as well as the others. If Jesus didn't care about our minds, He wouldn't have wasted His breath to mention that factor.

What other things do you feel is a danger to our potency and power as Christians?