There is a famous picture of a placard held up by a demonstrator who was protesting vociferously against Donald Trump. The poster reads: 'Love Trumps Hate.' And then underneath, there are the words: 'F*** Trump.'

Presumably the irony of the tension between the two parts of that statement escaped the protester. But in a way his placard neatly encapsulates the dilemma in which many people find themselves in this era of contentious politics in both the US, the UK and elsewhere.

Wherever we stand on various issues – whether in relation to Trump, Brexit, Jeremy Corbyn, Scottish independence, the Northern Ireland election or anything else – we find much that unsettles us in civil society. Most people feel they want to say something – but struggle to know how, as that protester's message illustrates.

This is where Jesus' teaching on God and Caesar is so helpful. He is approached by some religious leaders seeking to trap him with a question which they hope will prove either that Jesus is a Roman sympathiser (which will alienate him from the crowds) or an anti-Roman revolutionary (in which case he will be in trouble with the authorities).

'Teacher,' they ask, 'is it lawful to pay taxes to the emperor, or not?' (Mark 12:14). Jesus, masterfully, asks them to produce a coin, which they duly do, and then remarks – perhaps while looking them in the eye with a mix of weariness, humour and rebuke: 'Render to Caesar the things that are Caesar's, and to God the things that are God's.' But what, now, does that mean in practice? Here are four suggestions:

1. Courtesy in our language. I suggest we should speak of leaders – even if we disagree with them – with the courtesy to which their office entitles them. Most of us are unlikely to carry posters saying 'F*** Trump' or similar. But there is a general coarsening of debate. For example, many people these days often refer to politicians they dislike simply by their surname. But we might, for example, want to give them the courtesy of their appropriate title whether that is 'Mr' Corbyn, 'Mrs' May, 'Ms' Sturgeon or 'Secretary' Clinton. These things make a difference.

2. Acceptance of election results. After the election of Donald Trump, one strand of protest revolved around the slogan 'Not My President'. But he was – and is – exactly that. It's true he won a minority of the popular vote, but he did win 30 of the 50 states. The point is that under the commonly-accepted US election system he legitimately gained office. Now we might feel the system should be changed, and campaign for that; but just because it throws up a result we don't like, it doesn't as Christians mean we can reject it.

Here in the UK I happen to believe our electoral system is deeply flawed, and indeed voted to change it when we had a referendum a few years ago. But most people rejected that initiative – so as a Christian I accept both that result itself and the ongoing imperfection outcomes of a system I believe to be less than ideal.

3. Obeying the law. The most obvious application of Jesus' teaching is that we obey the law. We do, therefore, pay our dues. We do not indulge in tax evasion. We seek to be honest citizens in civic society, be that in big matters of state or small issues in the office.

4. Obeying God above all things. There will be occasions when we cannot, in good conscience, obey the law, because we believe that to do so involves disobeying God. This will, I think vary from believer to believer and situation to situation. What may be right for one person may be different for another; we have to respect one another's differing consciences.

The important thing is that we are conscious that the Lord's rule trumps all others. John Piper wrote: 'What is God's? The answer: Everything is God's. So the point seems to be: When you realise that all of life, including all of Caesar's rights and power and possessions, belong to God, then you will be in a proper frame of mind to render to Caesar what is Caesar's.'

Writing on Jesus' words here, Methodist statesman Donald English commented shrewdly 25 years ago: 'Governments need the reminder... that only God ultimately reigns, and that all policies should be worked out in relation to that. In particular one wonders whether the growing power and claims of nationalism around the world do not need sharp examination by this criterion from Jesus.' It was perhaps a prophetic comment.

David Baker is a former daily newspaper journalist now working as an Anglican minister in Sussex, England. The Rough Guide to Discipleship is a fortnightly series. Find him on Twitter @Baker_David_A