American theologian and ethicist Professor Stanley Hauerwas has hit out at Donald Trump and offered a stark challenge to the contemporary Church.

'Donald Trump is an idiot who wants you to be in his reality show', Hauerwas said. 'The challenge is not to let him dominate your life.'

The man Time Magazine once named as 'America's best theologian' was critical of Trump, but said that the president may remind the Church what it truly stands for. He was speaking this week at lectures for both the think tank Theos, and St Mellitus College, in London.

He said: 'Trump may not be good for America but he may be pretty good for the Church.

'Trump forces Christians to be a people of justice rather than looking for the state to give justice.'

He added a line emblematic of his theology: 'The first task of the Church is not to make the world more just but to make the world more the world.'

He explained: 'You only know that there is a world, if you know that there is an alternative to the world.' The Church embodies the witness of an alternative reality, the people of God, telling the world to "come home".'

A committed pacifist, Hauerwas has made consistent criticisms throughout his career of American nationalism, militarism and capitalism – and particularly the notion of Christianity aligned with the state.

He said: 'America is a country that runs on fear...the strongest nation in the world runs on fear.'

In a time of fear, Trump offered safety, he said. Trump in his election campaign gave voice to people's pain, particularly in working class groups, over economic losses. Even if Trump's economic policies will hurt those people, Hauerwas said, 'recognition matters to them more than money'.

He later said: 'The state is one of God's good creations. It's not called to be a saviour.'

In contrast to the state, and 'the world', the Church must embody God's presence in the world. In simple terms, this means the renewal of congregational church life, of word and sacrament, and 'a people who have learned to love one another in a world that hardly knows what love is'.

Likewise, in a 'post-truth' world, Stanley, said perhaps the Church can become known as the community that tells the truth.

His philosophy of mission is simple, pointing to monastic contentment: 'When people can see Christians as happy people again, then churches will grow.'

Can you be a faithful Christian and a president? Hauerwas said no, though he said some can come close.

'Good Christians get to run for office once. If they do the right thing they won't be re-elected.'

Hauerwas describes the present moment as a 'very transitional time, no one is sure what Christianity is going to look like'. But, he says, there's no point getting anxious about it.

'In this time called Trump', as he puts it, Hauerwas calls the Church to remember what it is, who it is about, and to hold on to that costly call – for the sake of the world.

Hauerwas' lecture for Theos can be heard here.

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