Tim Farron's resignation as the leader of the Liberal Democrats – for which he cited his own faith convictions – can make for a depressing read. Is there any hope for Christians in politics?

Farron cited an irreconcilable chasm between living faithfully as a Christian, and leading a progressive political party. As he put it: 'To be a political leader – especially of a progressive, liberal party in 2017 – and to live as a committed Christian, to hold faithfully to the Bible's teaching, has felt impossible for me.'

Now he's resigned, because of his faith, is it game over for Christians in the public sphere? Some young believers may take his fall as a sign that Christians, particularly evangelicals, are not welcome in politics, much as they might want to be there.

Farron noted that 'A better, wiser person than me may have been able to...have remained faithful to Christ while leading a political party in the current environment.' In that more hopeful light, and on the assumption that Christians should distance themselves from the world but engage in, love and serve it, here are six contemporary leaders who've been public about their faith.

1. Barack Obama

Despite facing numerous conspiracy theories that he was a Muslim, US president Barack Obama has long been a committed Christian for whom faith is central.

At the 2011 Prayer Breakfast he said: 'When I wake in the morning, I wait on the Lord, and I ask him to give me the strength to do right by our country and its people. And when I go to bed at night I wait on the Lord, and I ask him to forgive me my sins, and look after my family and the American people, and make me an instrument of his will.

'I say these prayers hoping they will be answered, and I say these prayers knowing that I must work and must sacrifice and must serve to see them answered. But I also say these prayers knowing that the act of prayer itself is a source of strength. It's a reminder that our time on Earth is not just about us; that when we open ourselves to the possibility that God might have a larger purpose for our lives, there's a chance that somehow, in ways that we may never fully know, God will use us well.'

2. Theresa May

The daughter of a vicar, British PM Theresa May is also a regularly church-going Christian. In 2014 she told BBC Radio 4's Desert Island Discs that her faith does impact her politics, and put the hymn When I Survey The Wondrous Cross as one of her favourite songs. She added however that 'It's right that we don't flaunt these things here in British politics.'

She told LBC last month that faith helped her cope with the death of her parents and realising she herself couldn't have children: 'It's difficult to explain in simple words but actually the faith was there and did provide support for me through those difficult times.'

3. David Lammy

British Labour MP for Tottenham David Lammy has also be vocal about his faith and politics. Last year he spoke about how it was 'first and foremost as a Christian' that he opposed the renewal of Britain's nuclear arsenal through Trident submarines.

In May he told Christians in Canterbury: 'People of faith have the compass to navigate our way to a better society. We need to speak when we feel the burden on society is too great and when society needs reining back...Armed with the glorious story of Jesus Christ, this is our moment and time. We must set to work.'

4. Tony Blair

Christian and former British Prime Minister and Tony Blair once famously ducked questions about his faith and politics when his communications chief Alastair Campbell told the American interviewer: 'We don't do God'.

Nonetheless, Tony wrote in his memoir that 'I have always been more interested in religion than politics', and told The Globe and Mail that 'faith plays a far greater role in political leaders than you might think'.

He once wrote: 'For a politician, [faith]... means that you see the need for change around you and you accept your duty to do something. Christian belief means you cannot detach yourself from the world around you.' Then in this interview with Jeremy Paxman, a youthful Blair began by saying he didn't like to 'make a big thing of' faith. But he went on to say: 'Of course, I'm a person...with a character and part of my character is what I believe in and part of my beliefs is a religious conviction.'

5. Angela Merkel

The German chancellor and TIME magazine's Person of the Year 2015 may not put her piety in the spotlight, but she has a Christian faith that religious commentator Nick Spencer calls 'deep, genuine and important'.

She said in 2012: 'I am a member of the evangelical church. I believe in God and religion is also my constant companion, and has been for the whole of my life...We as Christians should above all not be afraid of standing up for our beliefs.'

6. Jimmy Carter

Former US president Jimmy Carter may no longer take the centre stage in politics, but his philosophy on faith and politics continues to inspire many. Facing cancer in 2015, he declared that his life was 'in the hands of God, whom I worship'.

He once summed up his life motivation: 'I have one life and one chance to make it count for something... I'm free to choose what that something is, and the something I've chosen is my faith. Now, my faith goes beyond theology and religion and requires considerable work and effort. My faith demands – this is not optional – my faith demands that I do whatever I can, wherever I am, whenever I can, for as long as I can with whatever I have to try to make a difference.'

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