This week there has been a row within the Labour Party about the controversial two-child benefit cap. The cap means that families on Universal Credit receive no additional payments for third or subsequent children. Labour has said that it is a dreadful policy but that it cannot afford to scrap it in current circumstances.

The Conservative government's original stated aim of the policy (as well as saving money) was to ensure that families in receipt of means-tested benefits "should face the same financial choices about having children as those supporting themselves solely through work". And many people do support the policy. The Fabian Society – with close ties to the Labour party - found that more than half the public were in favour of the cap.

People believe that parents should take responsibility for how many children they have and can afford. However, the Covid pandemic followed by a cost of living crisis means that many people have lost their jobs, fallen ill, or are simply finding their earnings no longer cover their outgoings. The Child Poverty Action Group found that 71% of poor children live in working families, and that this policy has in fact actively pushed families into poverty.

These issues are far more complex than a tabloid headline would suggest, and such broad-brush policies always have unintended consequences. Shockingly, the British Pregnancy Advisory Service has warned that the two child cap has led to more abortions, as women fear they cannot afford to raise another child.

Christians on the Left – Labour's Christian group - have tweeted to say that they believe the two child cap is incompatible with ending child poverty and is a key driver of food bank use. In my podcast last week, we talked about the importance of long term planning for future generations. The Child Poverty Action Group has estimated that child poverty costs the UK nearly £40 billion per year in terms of lost earnings and income tax, unemployment benefits, and additional spending on public services due to child poverty, such as Pupil Premium and children's social services.

Of course there will always be those who abuse the system. But children are always the innocent parties, and I'm not sure we should punish them for the choices of their parents. And in any event, today's economic circumstances are pushing people onto benefits who have never needed them before. Yet at the same time, can we afford to keep supporting them?

The Office for Budget Responsibility has predicted that UK national debt will be three times our GDP in 50 years' time. The head of the Institute for Fiscal Studies, Paul Johnson, noted that "we cannot begin to afford the current welfare state without very big tax rises" and "if we want to avoid big tax rises we need to dramatically reduce expectations of what the government does".

Of course Christians will take different views on what should be done. The author of the two-child policy, Iain Duncan Smith, is a Christian, and did so in order to encourage personal responsibility. But the Bishop of Durham recently piloted a Private Member's Bill through the House of Lords to abolish it, calling it "immoral". So where and how do we draw the lines?

As Christians weigh up different parties' proposals, there are three questions we can ask: firstly, do we see in their approach a sense of compassion for the poor and marginalised? 1 John 3:17 says: "If anyone has material possessions and sees a brother or sister in need but has no pity on them, how can the love of God be in that person?"

Secondly, do we see a relational approach to policy? We are all part of families and communities, with a responsibility towards one another. Are people viewed as human beings with infinite worth, with commitments to others, or treated as isolated individuals?

Thirdly, are the causes of problems being addressed as well as the consequences? Picking up the pieces might cost more than tackling the reasons why people fall into poverty in the first place. Ultimately our welfare state, like our other public services, was designed for a different time. There's a limit to what the state can do. But the recent Theos report called "A Torn Safety Net" warns that the Covid pandemic and rising cost of living means that faith and community groups – who have been offering so much provision in their local areas – are also reaching the end of their resources as their supporters can no longer afford to give so much of their time and money.

But our God is infinitely creative, and we know he cares deeply for those who are struggling. In the words of Psalm 113:7: "He raises the poor from the dust and lifts the needy from the ash heap". So let's pray that he will raise up thinkers and policy makers who can lay hold of his inspiration and compassion, to find new approaches and solutions to these issues which may seem insurmountable. And let's be encouraged by Ephesians 3:20 that he "is able to do immeasurably more than all we ask or imagine, according to his power that is at work within us".

Tim Farron has been the Member of Parliament for Westmorland and Lonsdale since 2005, and served as the Leader of the Liberal Democrat Party from 2015 to 2017.Tim is also the host of Premier's 'A Mucky Business' podcast. His new book A Mucky Business: Why Christians should get involved in politics is published in November.