Building the right walls.

CFC's journey through Nehemiah has posed us some searching questions.
While Nehemiah built literal walls they were reflective of the Glory of God. When Jerusalem was in ruins it said everything to the heathen nations about the power of Jehovah. That's why he got passionate about the rebuilding. It was about God.
To help connect us with those who don't share our beliefs or values, what walls should come down and what walls should we keep or rebuild?
The church often has the knack of picking the wrong walls to build. What would you keep, absolutely no compromise and which ones would you knock down for ever?