On 7 May the UK goes to the polls for the general election. Whoever assumes power will have a profound influence in shaping public policy in matters which affect us, our families, churches, patients and colleagues. Some claim that politics and religion should not mix – but God is intimately involved in politics. He is sovereign over the rise and fall of nations. (1) He establishes governing authorities, and holds them ultimately accountable. (2) As Christians, we should both pray for our political leaders (3) and be subject to them. (4) But God has also given us a part to play in who actually exercises civil authority.

Each of us, before God and in good conscience, must make our own decisions about voting; but we have a duty before God to ensure that we exercise our votes wisely, thoughtfully and in an informed way. For some, the key question will be about who they would prefer as prime minister for the next five years. For others it will be a matter of which specific issues they care about most and how the various parties and candidates stand on these. Whether we choose to vote for, or against, a particular party or candidate, or on a specific issue, there are lots of resources to help us reach our decision.

The Economist/IPSOS Mori Issues Index ranks political issues in order of importance as seen by the British public. In September 2014 race relations/immigration was top with 39% followed by the economy (30%) and the NHS (25%). (5) The next seven were defence (23%), unemployment (21%), education (16%), housing (15%), crime (14%), poverty (13%) and inflation (11%).

The BBC's Manifesto Watch helpfully outlines where the seven main parties stand on each of these ten top issues. (6) With the economy and the NHS ranking second and third respectively, it is also worth remembering how the two are closely interrelated. Most CMF members are employed by the NHS and almost all of us, along with our patients, rely on it for our healthcare.

In June 2014 the NHS was declared the best healthcare system in the world by an international panel of experts. They rated its care superior to countries which spend far more on health. (7) The Commonwealth Fund, a highly respected Washington-based foundation, examined an array of evidence about performance in eleven countries, including detailed data from patients, doctors and the World Health Organisation. In their study, the UK came first out of the eleven countries in eight of the eleven measures of care. It got top place on measures including providing effective care, safe care, co-ordinated care and patient-centred care. The fund also rated the NHS best for giving access to care and efficient use of resources.

The 30-page report Mirror, Mirror on the Wall concluded, 'The United Kingdom ranks first overall, scoring highest on quality, access and efficiency'. (8) But financial pressures are squeezing the ability of the NHS to deliver. The Nuffield Trust has shown that because of population growth, ageing and cost increases, by 2020–21 the NHS will require some £30bn (25%) more than it is getting now just to maintain services at their present level. (9) But while real average NHS spending has increased by at least 3% per year since 1951, this has fallen to 0.75% per year since 2010. (10)

The major driver of this fall has been the UK's national debt, which is now at its highest peace-time level. When the coalition government took office in 2010 our total government debt was £811bn. (11) By December 2014 it had reached £1,483.3 billion (80.9% of GDP), a rise of over 80%, with much more to come. This rise is the result of accumulating annual deficits. Although the gap between annual government income and expenditure is gradually falling the total debt is paradoxically rising.

This national debt matters. It must be serviced with regular interest payments, diverting money from frontline public services. Even at rock-bottom interest rates, the government will spend almost half as much on debt interest in 2014/2015 as it will spend on the NHS (£52bn (12) cf £113bn (13)). As the national debt escalates, courtesy of £100bn-plus annual deficits, and as interest rates inevitably rise, we may yet end up spending more on government debt service than on health. This situation clearly cannot continue and a key question must be what kind of government is best placed to put our balance of payments in order. Debt is a moral issue with serious consequences for families, communities and countries.

We also face other moral threats in the health service, not least the legalisation of assisted suicide. On this and other conscience issues we will want to know where our own MP stands. Recent parliamentary votes on same-sex marriage, sex-selective abortion and three parent embryos, for example, have been deeply disturbing. The Public Whip website (14) tells you exactly how your own MP has voted on a range of crucial issues and The Christian Institute (15) and CARE (16) have also compiled valuable online databases on past voting records.

Let's make use of all this valuable information in making an informed vote that really counts this May. But let's also pray for the future of our country, and our health service.