Back to Jerusalem works in closed countries, but no country is truly closed, nor is any people group or religious system fully closed. The reason is that it is impossible for any community to exist without reference to anyone else.

North Korea is a case in point. Self-reliance is a core element of their ideology, but in reality this is just propaganda. The nation cannot produce enough food, fuel, medicine or building materials for meeting the needs of their own people.

That means the regime must get creative in acquiring foreign currency to buy these items. One of the ways is by sending groups of labourers to other nations to work in places like shipyards, mines and restaurants. Their earnings go directly to the government.

Within North Korea, the regime keeps its people shielded from outside influences in ways that are often brutally efficient. Outside the country it tries to do the same, but within a completely different environment; the usual tactics of isolating people are a lot harder to implement. As a result, missionaries find ways to engage with these labour communities and share the gospel with them.

Every year we meet with a group of hackers from all walks of life and different countries to discuss ideas on how to get the gospel into places that seem closed, using technology. One of the participants remarked that closed systems have walls, but there are always doors in those walls that are intentionally left in there by the system that built the walls, because they need some kind of engagement with the outside world.

One way of getting in is scaling walls. For example, by outsmarting the computer systems that keep people from accessing outside information, or by entering physical spaces covertly, to bring in Bibles. However, we can also find the doors that are built into these walls, making use of the inevitable points of engagements that closed systems and areas have in order to survive. For example, like using trade to move funds for mission projects, reaching international students who can take the gospel back home, investing in businesses that meet the needs of the local economy, or train maids and nannies to serve rich families in closed countries as ambassadors of the gospel.

But ultimately we have to realise the real walls are not digital or legal, but spiritual. We can try to scale them in the name of Jesus, or sneak through the doors as carriers of the gospel, but it is prayer that makes them come down. And it is Jesus himself who will open the doors that no one can shut. (Rev 3:7,8)