I was talking to a friend about the challenges that we Christians face today when he said, 'We are swimming against the current – the world has lost its reason.' The phrase struck me and I've been pondering it.

The first phrase – 'swimming against the current' – is a truth that we Christian's face opposition from our culture that opposes our faith, convictions and values. In Britain the 'cultural current' has been flowing strongly against the Christian faith for over a century. There is much in the Bible about how God's people must resist the force imposed by the world about them. We are to be different: we must always go against the flow, stand firm and 'march to the beat of a different drum'.

On considering the second thought – 'the world has lost its reason' – I realised that there are now new complexities in swimming against the current. While we might once have imagined that we were engaged in swimming up some slow, steady flowing river, a more realistic image today is that we are in some windswept tidal estuary in which the waters swirl chaotically. Today, the forces pressing upon us are strong in one direction, tomorrow they are going in another direction. The world has changed, and with it the currents we face.

Here I think we need to understand the culture that we face in the West today. What we call Western 'culture' did not arise in a vacuum but was formed by the Christian faith over 2,000 years. At its heart was a belief in Jesus and his revelation in the Bible. With this came a morality – a worldview – in which such things as truth, charity, justice, humility and marriage were valued, as was the worth of every individual, however poor or frail. Christianity gave the West values, principles and standards. Life had a rule book.

Around 250 years ago philosophers began undermining the fundamentals of the faith, and soon culture – art, music, literature and, increasingly, beliefs in general – followed them. The values of Christianity are strong and enduring but, as the tree of faith was left to wither, so, inevitably, its fruit failed. Most of those who sought the eradication of Christianity believed that, with its influence removed, the world now liberated from God would enjoy a new freedom. Of course, it proved otherwise. The loss of Christianity at the core of our culture has left a confused, troubled vacuum in which all sorts of ideas and movements, some secular and some spiritual, compete aggressively for influence.

In fact the Western world has indeed 'lost its reason' in two senses. It has lost its rationale, its reason for existence; it is now ignorant not only of what's right and wrong but even of what it stands for. Yet it has also 'lost its reason' because it has become an intellectual chaos in which nothing is certain except uncertainty. The mood today is one of confusion and confrontation; whether in politics, social thinking or philosophy there is now no quiet middle ground of consensus but only noisy extremes and bitter disagreement. Are we in favour of consumption or conservation, integration or individualism, liberalisation or legislation, wealth or welfare? The result is that Christians today no longer face a single oncoming hostile army but are instead caught up in a cultural civil war with crossfire coming from every direction. We face not just a current but many currents, ever changing and coming from many different directions.

So how are we Christians to respond to this world in which we find ourselves buffeted by a range of unpredictable and powerful currents? Let me offer you four thoughts.

We must live in reality. We need to think realistically about the world and our faith. With regard to the world, we cannot be naïve. The changes that we see are so deep and wide that outside some remarkable intervention by God in revival (oh, I pray it may be so!), they are not going to be easily and quickly reversed. Instead we must discern which of the many currents affecting us are the most dangerous. After all, it may be that our most serious threat comes not from that current giving the noisy, visible waves but instead from some quieter flow moving at depth. Yet it is not all gloom. As God's people found in the past, our opposition is divided and battling against itself. We too must balance any awareness of threats with a confident faith in the One in whom we trust – the Lord Jesus Christ. This world, and indeed time itself, is in our heavenly Father's hands. We can have faith that the Great Shepherd will not desert his sheep, especially when, in the darkness, the wolves are howling.

We must pursue strategy. In these volatile times there's a lot of fear about, and not just among Christians. Allies today can easily be opponents tomorrow. From a Christian point of view, there's a lot to be said for that popular phrase, 'Don't panic.' Fear is not only bad but it also fuels unwise decisions. We must respond to the world we face in a way that is both spiritual and strategic. If we must fight, let it be the right battle at the right time. There are some issues where we have no option but to stand our ground: it is the 'right hill to die on'. Yet there are other issues that we might decide are negotiable or even unimportant.

We must hold on to integrity. Perhaps the real threat of our times is not that Christians become overcome by the world but that, during combat, they become like the world. That sobering comment of our Lord, 'What good will it be for someone to gain the whole world, yet forfeit their soul?' (Matthew 16:26 NIV) applies not just to individuals, but to the church. To win a battle over the world in a worldly, underhand way, is to be defeated.

Finally, we need to use the opportunity. Here, I speak as an evangelist. Christians under pressure can retreat into sanctified circles that gaze inwards, and close the doors against the outside world. We cannot do this! As Christians, and as churches, we either witness or we decline. But let me encourage you: one feature of our present troubled world is that it is full of discontented people. Across the political and social spectrum, there are many who, often amid tears, have found their dreams for a better world broken. A growing number are, like the prodigal son in the 'far country', wondering whether it might not be time to return to the home and the Father that they rejected.

As believers in Christ we now find ourselves struggling against shifting currents, varying winds and changing tides. Yet above all, we must remember that our Lord is the master of the stormiest of waters and we can trust him, in his time, to bring us safe to port. We remember too his words in John 16:33 (NIV): 'I have told you these things, so that in me you may have peace. In this world you will have trouble. But take heart! I have overcome the world.' Amen!

Canon J.John is the Director of Philo Trust. Visit his website at www.canonjjohn.com or follow him on Facebook, Instagram or Twitter.