The Israeli historian Yuval Noah Harari is this generation's 'must have' writer if you want to show just how in touch you are with modern society.

His Sapiens and Homo Deus have sold, and continue to sell in their millions. He is the guru of the techno elites from Bill Gates to the current masters of Google and others in Silicon Valley.

Sapiens gives us a history of humanity from an evolutionary perspective. It's basic thesis is that that there have been three big revolutions in human history; the Cognitive, the Agricultural and the Scientific.

Homo Deus is his attempt to project on to the future. He looks at the dreams, fears and possibilities for the future.

His vision of the future is to my mind, somewhat depressing and dystopian – human beings will become in effect superior machines and there will be no need for the 'useless' class. The next stage of evolution is for humanity to become God. Where have we heard that promise before?!

Harari has got himself into a spot of bother though. His latest book – 21 lessons for the 21st Century is about the present. As with the other books there is much that is stimulating and provocative, but in a book that warns about 'fake news' and argues for clarity, Harari has confused his own message.

The trouble is that the Russian edition is different from the American edition. In the latter, Russia is criticised for its invasion of Crimea and the post truth aspects of its society. In the former that criticism is removed and replaced with one of Donald Trump and American society. Harari justifies this by saying that the Russians asked for it and as he wants to sell books in Russia, then he had to go along with it. But that raises several serious questions.

If you are claiming to be a prophet of the future, or at the very least an impartial cultural observer and analyst, then you should not tailor your message to suit the governing classes of whatever society you are writing about.

Harari has fallen prey to the temptation of so many Christian preachers and prophets. Rather than just say the Word of the Lord to the culture, we are tempted to adapt the message, rewrite the Bible and proclaim it in such a way that will not offend and will ensure us a hearing.

Whilst it is surely right that we must consider the culture and how to speak into it in a relevant way, it becomes disastrous when we change the message in order to suit the hearers. Therein lies the hypocrisy that Jesus so despises.

How often do we proclaim a Jesus that is a reflection of our culture and what we want him to be, rather than Jesus as he really is – the Jesus given to us in the Scriptures?

Perhaps Christian writers and preachers can learn another lesson from Harari? His third book has generally been reviewed as the worst of the three because it is largely a rehash of the arguments in the previous two. I wonder how often we end up just rehashing old stuff in order to feed the beast that is content demand! Maybe if we have nothing fresh to say, we should say nothing!

John Crace in the Guardian does an excellent job of summarizing Harari's argument so that we can digest it. "No one knows what the future will look like. Humans like to tell themselves stories, be they in the form of religion or political ideologies, such as nationalism, communism and liberalism. But none of these can adequately prepare us for what may happen in the next 50 years. New technology and climate change might make the world more different than we can possibly imagine. So we had better keep an open mind and hope for the best." 

This is a great summary of the Humanist 'hope'. No one knows what the future will hold, so all we can do is keep and open mind and hope for the best. It's little wonder that Harari devotes so much time at the end of his book to 'meditation'. I do a weekly podcast (Quantum of the Wee Flea) in which like Harari, we look at and think about current trends.

A few weeks ago a friendly critic pointed out that at times it could come across as a wee bit despairing and hopeless. It was a sore one to take – but he was right. Just giving an analysis is not enough – you have to give people hope. Real hope.

Harari's 'hope for the best and meditate' is not good enough. The Christian hope is very different because it is 'sure and certain' (Hebrews 11:1). Harari sees a future where humans will merge with robots – and in effect become robots on a decaying earth.

Paul in Romans 8 sees a very different hope. Renewed bodies in a renewed earth. The groaning is over. Here we have the first fruits of the Spirit, we are born again and given eternal life, but we live in fading bodies. Our hope is for the redemption of our bodies and restoration in the new heavens and the new earth.

The Christian hope is as different from the dystopian horror of Harari as fine dining is from junk food. This is Good News – we don't need to hide it or tailor it to suit our cultures. Rather we turn our cultures upside down by proclaiming it. For us the best is yet to be. In Christ alone our hope is found. He is our light, our strength, our song!

David Robertson is Director of Third Space at the City Bible Forum in Sydney, Australia