One of the most exciting things about being a Christian is that our God is a God of surprises. Sometimes he opens your eyes to see what he is doing and it leaves you amazed.

When I first started to take a peek into the world of Christians involved in politics, my hopes weren't high. The varying views that different Christians hold on the state of our society mixed with political loyalty sounded like a recipe for trouble and conflict, but I was proved utterly wrong. Some of the many Christians I've met who are involved in the political sphere at various levels are among the most godly people I know.

This was demonstrated to me once again when I attended last weekend's inaugural Christians in Politics conference. Christians in Politics is the umbrella organisation of the Conservative Christian Fellowship, Christians on the Left and the Liberal Democrat Christian Forum. Here we had a diverse group of Christians of all political persuasions coming together, but instead of political tribalism taking the centre ground there was an incredible atmosphere of unity that I've rarely experienced among Christians. (Harry Farley's write-up demonstrates just how surprised some delegates were by this.)

So many of the people I met at the weekend clearly love God, and the desire to fully live for him has led some of them to become MPs, councillors and policy advisers. They have chosen to go down that route not because of any personal desire to exert control over the lives of others, but because they truly have a longing to see God moving in the corridors of power and throughout our nation. They see themselves as advocates for the Kingdom of Heaven – not Christians who happen to be involved in politics, but servants of God called to bring his light into the places that shape our culture and society.

This was a key theme that I tapped into during a talk that I gave: if we want to see our towns, cities and villages transformed for the better, then we need to become God's agents of change. This is the same for each one of us, irrespective of who we are or what we do. If we consider ourselves to be Christians then we need to be influencers rather than be influenced by society; to pray and act rather than sit on our backsides and hope God will sort it all out. Neither can we compartmentalise jobs. To say that I have an interest in justice issues but that evangelism is for others is to misunderstand the very nature of Jesus' teaching.

In Matthew's Gospel, Jesus tells the disciples to go and make disciples in every nation. There is no getting away from this call to every Christian, but much earlier on in Jesus' ministry he gave his Sermon on the Mount in which he said this:

"Blessed are those who hunger and thirst for righteousness,
for they will be filled.
Blessed are the merciful,
for they will be shown mercy.
Blessed are the pure in heart,
for they will see God.

Blessed are the peacemakers,
for they will be called children of God."

Jesus is talking here about the way that we act and live and how we should be changing the world. To reinforce this, in the following passage Jesus describes his followers as the salt of the earth and the light of the world. We are not to hide what we have or to be passive in our faith. He concludes this section by saying:

"In the same way, let your light shine before others, that they may see your good deeds and glorify your Father in heaven."

To glorify God is to let our faith flow through every part of our life to the point where others can't help but notice. Words are good, but it is the deeds that often have the greatest impact. We should expect to have an effect on others by our actions and yet too often I see Christians quite happy to be influenced by those around them rather than being the influencers and shapers.

I put this down to two reasons:

1. Churches still being too focused on what goes on inside their walls, or activities considered to be 'Christian' ministry, i.e. doing work for churches and Christian organisations. How many churches have photos of missionaries working abroad on their notice boards and hold regular prayers for them at the front, but barely mention the concept of mission in the workplace or at the school gate? How often do current issues in politics or the media find their way into Sunday sermons?

2. Lack of confidence. We repeatedly hear messages through the media that religion is a source of conflict or is outdated and irrelevant. It's not easy outing yourself as a Christian, and if you find it a struggle to explain what your faith is all about or if you've been led to believe that religion should be a private matter then it's far easier to just shut up and keep it to yourself.

It's a tragic waste when, for whatever reason, Christians hide their light, because there is copious evidence that great things can be achieved when the opposite happens. Let's not forget the massive impact on millions of lives through the Jubilee 2000 and Make Poverty History campaigns. Or we could talk about foodbanks, the drive towards establishing a living wage and the Modern Slavery Act. None of these would have come about if it wasn't for Christians in this country looking to change situations both here and abroad for the better. And these examples are just the tip of the iceberg. There are countless examples of Christians in business, education, the arts and beyond doing wonderful things.

We might think that we aren't important or clever enough to make a difference, but there are plenty of examples in the Bible of God using people who would have seen themselves as nobodies to do his will. What marks out people like Ruth, David, Peter and most of the apostles is their willingness to give up everything for the sake of doing God's will. It was the same for me four years ago when I made that commitment at a festival. Not long afterwards, I felt a very real calling by God to be a voice in society. I had no experience of this and a pretty ordinary life, but despite hating English at school, I began writing a blog discussing news stories from a Christian perspective. Since then God has continually dropped opportunities into my lap and has opened doors all over the place. Hundreds of thousands of people have now read my work, and now and then I get asked to appear on television and radio programmes. MPs, Lords, Bishops, journalists and church leaders have taken notice of what I've said and even though I have no idea to the extent of what God has done through me, I know it has made a difference.

As I was spending time at the Christians in Politics conference I couldn't help but consider the potential around me. When we step out in faith beyond our comfort zones, putting ourselves in God's hands and relying on the power of his Holy Spirit, not only do we find ourselves increasingly united with others who share the same passion to serve, but it is also inevitable that we will see God moving too. If the bitter divides of politics can be melted through the love of Christ, then surely this is a sign that so much more can be achieved in other spheres of society and culture for the sake of the God's Kingdom, if only we are willing to fix our eyes on the author of salvation and respond accordingly.

Gillan Scott regularly writes about the relationship between Christianity and society. He is deputy editor at archbishopcranmer.com. You can follow him on Twitter @gillan_scott.