I am a firm believer that God alone is the source of truth, that His truth is absolute, and that absolute truth is found in God's Word. However, I don't believe that God has limited us to finding His truth only in His Word.
In fact, the Bible itself tells us that God has infused both His creation and our conscience with the truth about Him
I just finished Jim Collins' excellent book, Good to Great. It's not about the Bible; it's about how to turn a good company into a great one. But many of the principles he presents are truth. In fact, out of the 80 sections that I highlighted in my copy of the book, next to 25 of them I wrote at least one Bible reference containing a direct parallel. And many of the rest were similar to Bible principles. I just didn't think of an exact verse right away.
The same principles that apply to growing a great company apply to growing a great Christian and growing a great church. In fact, that sounds like a great teaching series. Stay tuned!