I have to admit that there's one place in the gospels where, despite Jesus' critique of them, I do have some sympathy for the Pharisees. In Matthew 16:3 Jesus castigates them for failing to read the signs of the times. I have some sympathy with them because those signs of the times aren't always that easy to read. We live in a rapidly changing world that seems to be increasingly unstable and uncertain. Just what is going on?

In Church Mission Society – and indeed in the Church as a whole – we have to be students of the times in which we live. Good practice in mission is always shaped by context. We have to ask, 'How can we faithfully follow Jesus in this place and at this time?' The principle of incarnation always forces us to ask that question.

There is one sign of the times which I want particularly to highlight, because in truth it's critical for mission. But before doing so I ought to say that I'm concentrating on a western phenomenon, which may not apply in every global context – though I suspect that its influence will be felt far afield. But, that said, here in the West, truth, as a concept, is increasingly undervalued. That's particularly ironic in a culture founded on the triple pillars of the Renaissance, the Reformation and the Enlightenment.

It's ironic, but nonetheless true. We hear a lot today about 'fake news' and 'alternative facts'. Just a couple of weeks the head of the UK statistics agency had to take the Foreign Secretary to task for continuing to overestimate radically the amount the UK pays to the EU. Not long before that the President of the United States was roundly condemned for a selective re-telling of his own words following the demonstrations and death at Charlottesville.

In truth we should not be surprised. At New Wine this year Michael Lloyd, Principle of Wycliffe Hall suggested that when a culture turned its back on the one true God and embraced many 'gods' then multiple versions of the truth would emerge. And so we see.

But lest we think it's only 'out there' I fear we fool ourselves. Not many weeks ago a prominent Christian website reported General Synod as having taken a decision that it in fact had not done.

I fear we're witnessing a phenomenon in which a number of overarching narratives are being constructed (whether that's to deny climate change, or to assert constant 'liberal slippage' in the church) and the facts are then manipulated to fit. So no longer does truth define the narrative; the narrative defines truth – or what purports to be truth.

But how do we react? If I'm honest I feel a good of outrage at the blatant peddling of falsehoods. But what good is my outrage to anyone else? (And what good does it do to me?!). There is, I am sure, a better way.

Paul tells the Ephesians to 'speak the truth in love' so that we will 'grow up in every way into Christ the head' (Ephesians 4:15). So we need to be uncompromising speakers of truth: 'Tell the truth and shame the devil' runs the old adage, and there's a lot of truth in that, not least as he is, in Jesus' words, 'the Father of lies' (John 8:44).

But that is not enough. We're to 'speak the truth', yes. But we're to do so 'in love'. And not doing so is not an option.

That does not water down our commitment to truth. Not at all: we're to be 100% people of truth. But we're to be 100% people of love as well, with no compromise on either side of the equation.

Our commitment to truth and love must be complete and uncompromised. It is so in Jesus and must be nothing less so in those who seek to serve him. Jesus was not a constructor of a convenient narrative: he fearlessly followed his Father's will, and did not count the cost in so doing. So must those who would be his disciples.

Rev Philip Mounstephen is executive leader of Church Mission Society.