Boris Johnson has dramatically resigned as an MP ahead of a damning report by the Commons Privileges Committee into whether he knowingly misled Parliament over the Partygate affair. Former Culture Secretary Nadine Dorries and another ally Nigel Adams also resigned, kicking off – as things stand – three by-elections at a time when the Conservatives are doing dreadfully in the polls.

Elsewhere, former US President Donald Trump has been indicted with 37 criminal counts for allegedly mishandling classified documents, and former SNP Leader Nicola Sturgeon was arrested in connection with an investigation into mishandling of the party's finances.

All in all, these events certainly vindicate the title of my podcast, A Mucky Business – and my book of the same name! Politics continues to be a thoroughly mucky business.

We could spend time delving into the details of these events, and emphasising the importance of integrity, justice and forgiveness, but I have already said similar things in response to the Boris Scandals part 1, 2 and 3. I'm not convinced you need to hear them again!

So instead, I want to think about why – despite all the muck – Christians should still be getting stuck into politics! And many are. Last week we spoke to Labour Parliamentary candidate David Lawrence, and over the coming weeks I'll be interviewing Christian candidates from the Conservative and Liberal Democrat parties who feel called to become MPs and who, perhaps amazingly, still want to do the job!

So let's remind ourselves why we still need to engage. Firstly, God is bigger than politics! The Bible is not a manifesto, where we sign on the dotted line and pay our membership fee. Political ideologies can help us make sense of the world and give us an approach for organising society – and political parties are vehicles for putting these ideas into practice. But politics cannot ultimately save us.

By contrast, becoming a Christian is completely ego-shattering because it tells us that we do not belong to ourselves, but that we are all joined to God's greater story of redemption and salvation for the whole world.

And God's plan is not a vague, distant and abstract one. He promises one day to redeem all things, not by whisking us away to live on a cloud, but by bringing together a new heaven and a new earth. He did not withdraw from the mess that we have made of his world.

In Isaiah 59:15-16, "the Lord looked and was displeased that there was no justice ... He was appalled that there was no one to intervene."

So he intervened himself, in bodily form. Through Jesus, he chose to enter into the world and to act from within it to put all things right. And in the Gospels we see that, yes, Jesus came to save souls, and that he also healed and fed people, and cared for their physical needs. The New Testament regularly speaks of Jesus' compassion for people's physical and emotional well being as well as for their spiritual situation.

As Jesus came to serve, we are also called to serve others, and with the same attitude of faithfulness, compassion and self-sacrifice.

Through politics, we serve God by serving others in our communities and beyond and by our conduct in the public square. Society needs leadership, governments have to exist and politicians follow some kind of ideology to come to decisions. All of this is imperfect. But if we don't show up and have a say in the decision making, we are effectively abdicating responsibility for who governs us and how.

There is no such thing as 'neutrality' in politics. Everyone brings their values and views to their politics. If Christians step away from this conversation, we will find that the decisions are entirely made by others on our behalf.

But, as I frequently say – to remind myself as much as others – we shouldn't be engaging in a belligerent or aggressive manner. We aren't called to despise or fear others. Instead we are called to stand in God's amazing grace and reflect that in all our attitudes and actions.

The gospel is incredible news. We are secure for eternity if we trust in Jesus. And we have a joyful and revolutionary hope that what we do now really does echo in eternity.

It is because of this hope that we can afford to love and give and care generously for those who are around us.

Therefore, as we seek to live in relationship with the God of the universe, politics gives us a chance to put his love for us into practice by loving and serving others.

It calls for us to show grace towards others as God has been gracious to us, and to "love because he first loved us." (1 John 4:19). By this we aim to show a better way and hope to clear away some of the muck in the process.

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.