Christians love the hymn Amazing Grace – but what does "grace" look like in action? And how would it change the world if its gentle yet radical power was fully unleashed?

Well, let me introduce you to a man who embodies the notion of grace. His name is Dr James Chin-Kyung Kim, and he is a 78-year-old Korean-American.

What is extraordinary about him is that he heads up a university in the North Korean capital Pyongyang for students who are the sons and daughters of that repressive land's ruling class.

What's even more amazing is that he is a Christian, and has made no secret of the fact to the state's fanatical communist rulers. Moreover, some years ago Dr Kim was imprisoned by the authorities while visiting the country, accused of being a spy – and sentenced to death.

He was reprieved after writing a letter declaring that once the execution had taken place he would like his organs to be used for medical purposes – an initiative that moved even North Korea's leaders so much they let him go and put him on a plane out of the country.

To cut short a long story, Dr Kim later went on to found a university in northern China. And when the North Koreans saw how outstanding it was they invited him back in to their own country to establish a similar institution there. And so the Pyongyang University of Science and Technology (PUST) was born, funded by American and South Korean Christian charities. Its 500 students are hand-picked by the authorities to receive training in a Western-style education with the aim of modernising their homeland.

Watching Dr Kim on the BBC TV Panorama programme in which he has just featured, it was hard not to be impressed by his radiant faith – he was seen singing "How great thou art" in the campus grounds as the film opened – and also by his grace. For despite his own experience in prison there, Dr Kim simply wants to do good – even in the restricted and repressive circumstances of North Korea. He can't of course stand up and lecture about his faith; nor can he challenge the system of government. What he can do is be a bearer of grace – of undeserved kindness – in one of the darkest places on the planet.

Critics who missed the programme might think he was naive, or a stooge – or even a fool. But no one who saw him or what he was doing would believe such things for a moment. Nor would they imagine he condoned the regime. They would be impressed by his bravery, by his vision – and by his compassion.

And if the North Korean regime doesn't "deserve" this grace – this wholly unmerited act of kindness – then nor, let us remember, do we. Yet it is still true God in Christ entered the world – a hostile world that would restrict and ultimately kill Him – to offer us unconditional kindness, forgiveness and hope. We too are recipients of grace.

Wherever you are reading this, it almost certainly isn't North Korea. Maybe you do live in an oppressive country where freedom is limited and faith is difficult. Or perhaps you live in a western country where Christianity is mocked but your life is reasonably comfortable and the main challenges are an irritating boss or neighbour, or what one person famously called "the multitude of petty annoyances".

Either way – Jesus has brought us amazing grace which we do not deserve. Dr Kim is bringing North Korea truly extraordinary grace in action. How can we too bring such transforming grace to those around us today?