On that fateful Friday morning when it became clear that the UK had voted for Brexit, some people were acclaiming June 23, 2016, as Britain's Independence Day.

But I believe that this date will go down in history as a Day of Infamy and that, from a Christian perspective, Brexit is a cause not for nationalistic celebration and triumph, but for nationwide soul-searching, which should include a strong note of lament and repentance.

The Brexit vote is a symptom of an underlying 'Crisis of Compassion' in British society. There is a chronic deficit of compassion, solidarity and even basic courtesy in our public life. Without the necessary foundation of compassion, society degenerates into what Thomas Hobbes called a "state of nature" in which, according to the proverb, homo homini lupus est – "a man is a wolf to another man". If you prefer a literary analogy, just think of William Golding's Lord of the Flies. The resurgence of the UK Independence Party and the dominance of hard-line Conservatism are clear manifestations of this regrettable phenomenon.

A related manifestation of this Crisis of Compassion is the resurgence of racist sentiments and fascist ideologies, which, if undetected and unresisted, will become progressively more mainstream. The Brexit vote has created alarming opportunities for the populists in UKIP, as well as for members of openly racist organisations like the BNP, EDL and Britain First. Dark undercurrents, which for decades had lain dormant, are now bubbling up to the surface of British public life. Racist attacks and hate crimes against immigrants and ethnic minorities have increased significantly since the Brexit vote.

British society is now reaping the seeds of fear and hate that have been sown by an irresponsible tabloid press. For decades, tabloid editors and columnists have been releasing toxins of fear, distrust, xenophobia and Euroscepticism into the bloodstream of British public life. As a result, many people in Britain, including those who profess Christian faith, have had their compassionate faculties inoculated by the constant assaults of the popular media on the values of truth, respect, dignity, humanity and compassion. Under a constant barrage of sensationalist headlines and malicious columns, tweets and social media posts, these moral and spiritual values have gradually eroded as power, greed, selfishness, falsehood and violence have triumphed over freedom, generosity, solidarity, truth and peace.

Apart from the racism and bigotry that fuelled the Leave campaign, one of the most disturbing aspects of the Brexit vote has been the realisation of just how irrelevant and meaningless the values of truth and integrity have become in an age which prizes sensationalist headlines and entertainment over boring facts. Therefore, another symptom of the Crisis of Compassion is the devaluation of truth. Some commentators have observed that we are living in a post-truth age, which means that we now live in a world ruled by technological gadgetry, celebrity culture, junk TV, lying politicians, PR spin and various forms of mind-numbing propaganda.

During the Referendum campaign the level of deceit reached such proportions that at times it almost seemed that the strategists of Vote Leave had been studying the diaries of Hitler's infamous Minister for Propaganda, Joseph Goebbels, who once said that, "If you tell a lie big enough and keep repeating it, people will eventually come to believe it." All of us have been diminished by the tactics of Vote Leave – for example, the mendacious pledges to give an extra £350 million per week to the NHS; to cut VAT; to increase pensions; to fund a multi-billion-pound investment in Britain's infrastructure; and to increase subsidies to the arts, sciences, research, farming and deprived regions of the UK.

In the coming years we will witness the terrible consequences of a Brexit vote that will exacerbate the Crisis of Compassion in our society.

The Crisis of Compassion is as prevalent among Christians as it is among the general population. When I spoke at churches in the lead up to the EU Referendum, I was shocked to hear Daily Mail headlines about "sponging asylum seekers", "benefit scroungers" and "violent Muslims" being parroted to me by sincere and godly Christian people. If you scratch beneath the surface of doctrinal correctness and polite Christian morality in many affluent church congregations, you discover a disturbing ignorance and an abyss of fear, suspicion, prejudice, islamophobia and even thinly-veiled racism. It's time that churches get real about these issues and challenge this kind of bigotry and ignorance.

Unfortunately, I see little ground for optimism in the coming years. Fate (call it 'Providence', if you prefer) has a propensity to wreak a terrible revenge on human weakness and folly and I think that the people of the UK will pay an incalculable price – not just in economic terms – for this monumental Brexit blunder. So I will not cry "peace, peace", when there is no peace, and I will speak plainly: the darkness is coming. The dusk has already set in and we are entering a long night that will become darker, colder – and a lot nastier.

In the midst of this Crisis of Compassion, it is time for the Christians to get out of their comfortable church cloisters. Christians need to take seriously their responsibility to stand in solidarity with those who will become the silent victims of the Brexit catastrophe and the new post-Brexit political configuration. These times call for renewed unity and vision and for resolute solidarity.

In times like these, more than ever Christians need to embrace their vocation to be salt and light and to infuse the society with the spiritual values of love, truth and solidarity. Most of all, every Christian should always be clear about one thing: that racism is not only a deplorable crime, but also a grievous sin. Racism is tantamount to blasphemy against the Holy Spirit. All human beings, regardless of nationality, ethnicity, skin colour, gender, religion, disability or sexuality, are God's image-bearers.

Moreover, those Christians who do not belong to any marginalised or minority group (black, immigrant, Muslim, gay, disabled, etc) should be especially sensitive to any attempt to scapegoat or demonise any of these people.

The only way to overcome the Crisis of Compassion is through resolute solidarity. Christians should glory in solidarity, because solidarity produces empathy and empathy produces compassion, which in turn produces hope, which rests on God's truth. And hope, ultimately, does not disappoint because one word of God's truth is greater than all the lies of the world.

Dr Joshua Searle is tutor in Theology and Public Thought at Spurgeon's College.