Closed church and open church

(This is something I'm talking about tomorrow at our Discussion and Discernment Day, and I'm writing it up as a blog post to make sure I know what I'm talking about.)
We often think of the church as a group where it's very clear who belongs and who doesn't belong. There's a clear distinction between those who are God's people and those who aren't.

The people who are in are believed to be marked by particular characteristics and behaviours such as attending church services, speaking politely and believing particular doctrines.
Is there anything wrong with that? I'll tell a story to explain why there might be some problems.
There's a guy who's possessed by demons, and rather than try to help him, his neighbours chain him up. Jesus comes along and frees him from the demons, and the people get upset - as though they would have preferred for the man to stay possessed. Naturally, he wants to leave the place and follow Jesus. But Jesus tells him to stay there and tell his neighbours about what happened. (That story is from here.)
So this guy might believe that anyone who follows Jesus is going to stay in their own town, and that anyone who leaves their town to follow Jesus isn't a true follower. So those who stay home are in; those who go are out.

One day another person turns up in his town, claiming to be a follower of Jesus. However, he says he didn't want to leave his town to follow Jesus (he wanted to stay and look after his family) was told by Jesus that he had to leave his home. (That happens here.) He might think that anyone who stays in their own town couldn't be a follower of Jesus.

So both of these people are going to think that the other is obviously not a follower of Jesus, even though they're both doing what Jesus asked them to do.
What if instead of looking at it as though some people are in and some are out, these two people looked at it as whether they were each moving closer to Jesus? Maybe they're both following Jesus, and growing more like Jesus, but they're doing the opposite thing to each other because they're coming from different directions?

This would explain why it might be good to tell poor people in Los Angeles that God wants them to be prosperous, but it might draw rich Melbournians away from Jesus. Although in a sense they'd be travelling in the same direction, they have different starting points.

In this kind of model, people are considered to be part of Jesus' church if they are moving closer to Jesus (becoming more like him), rather than if they fit various criteria.

No matter how far away from Jesus someone is, if they begin to move closer to him, the boundary extends to include them.

The first model, with its precise boundary, is like a farm that uses a fence to keep stock together. The second model is more like a farm in the desert that uses water to keep stock together. If the stock know that they need water, they'll never go too far from the water. Similarly, if people need Jesus, they will never stray to far from him.
Also, in this model, people who mightn't consider themselves to be Christians (but might still be growing closer to Jesus) might have something to offer Jesus' followers. Similarly, people might grow closer to Christ without choosing to adopt the label 'Christian'.