One of the bright spots of contemporary society is a popular podcast - The Rest is History - in which two historians, Tom Holland and Dominic Sandbrook, discuss a wide variety of historical events. Attending a packed-out theatre in Sydney with the two of them a couple of months ago was testimony to the demand for history that they have engendered, or uncovered.

From a Christian perspective it is also great that they do not ignore the spiritual – or what they tend to call 'the sacral'. So, it was with a great sense of anticipation that this week I looked forward to their five-part series on Luther. As a member of 'The Rest is History Club' I was able to binge it in advance of general broadcast and it was well worth it - entertaining, stimulating, informative and thought provoking as ever. However, it was also enlightening in that it demonstrated how little even the most sympathetic of commentators grasp what biblical Christianity is about.

Let's leave aside their inability to grasp the difference between the Catholic (transubstantiation), Lutheran (consubstantiation), Calvinist (spiritual presence) and Zwinglian (symbolic) views of communion – I doubt that many Christians would be able to articulate the differences. What astonished me was how they misunderstood some of the basic teachings of the Reformation.

Sandbrook stated that Christianity is what the Church says it is. He went on to say that if you are going by Scripture, then Scripture can mean whatever you want it to mean. He went further to say that the meaning of Scripture is plain is 'obvious tosh'. Except it is not obvious tosh. In fact, what the Westminster Confession of Faith calls the 'perspicuity' of the Scriptures, the clearness of the Scriptures, is a basic and rational doctrine of the Christian faith.

The Bible is actually clear on many things – that Christ died for our sins, that he was raised on the third day, that we all need forgiveness etc. The fact that there are difficulties, or that some people will misuse or misinterpret what is written no more invalidates the Bible than it would invalidate Tom and Dominic's history books. And their books were not inspired by the Holy Spirit!

Luther never taught that what the Church or Scriptures say does not really matter, but rather that there is individual conscience. He wrote a whole work, The Bondage Of The Will, on how human capacity was limited and why we need the Scriptures and the Spirit.

Reading Luther through such a radical individualistic lens led Sandbrook and Holland to the claim that the statement 'I don't know whether I believe in God, but I have a personal spirituality' was essentially Lutheran. It's all about 'living your truth'. That may be the current Western cultural fad, but the attempt to blame Luther for it, in order to have a historical theory for everything, is just wrong. Luther was not such a subjectivist. He believed that there was objective truth – and it was to be found in Christ and Scripture. It is not the case that Luther taught that you have to have this feeling that you are one of God's elect. Luther, along with most of Christianity, taught that while feelings were not unimportant, they were a result of having faith in the fact that Jesus Christ died on the cross and rose from the dead. The feeling may follow the faith, but having the feeling in and of yourself is not what makes you a Christian.

Another bizarre idea that stems from a historical/sociological theory, rather than theology or indeed historical fact, is that Protestantism leads to atheism. It's the old atheist meme – 'you don't believe in thousands of gods; you need to be like us and go just one god more'. It is seen as an inevitable progression: if we reject the absolute authority of the Catholic Church, then it is inevitable that we will reject the Bible, and therefore become atheists. It's an interesting theory, but demonstrably false, not least in the fact that hundreds of millions of people are Protestants today and still believe in God.

The argument that Protestantism leads to secularism has more truth to it, although it does depend on what you mean by secularism. If it simply means the separation of church and state, then that stems back to Jesus's radical words, 'give to Caesar what is Caesar's and to God what is God's' (Matthew 21:22). Larry Siedentop's Inventing The Individual, as well as Tom Holland's Dominion give us the background as to how Christianity as a whole invented modern secularism.

What astonished most in a five-programme series examining Luther and what he taught, was that Sandbrook and Holland left out his most important and radical doctrine – 'justification by faith alone'. Luther came to understand that we are not saved by our own works, righteousness, feelings or experience but by faith in Christ - and Christ alone. Once you grasp this it liberates you. Know the truth and the truth will make you free.

Sandbrook claimed that Luther was a narcissist and that it was all about him. He clearly had not read Luther himself, who claimed "while I slept, or drank Wittenberg beer with my friends ... the Word so greatly weakened the papacy that no prince or emperor ever inflicted such losses upon it. I did nothing; the Word did everything."

As we celebrate this Easter weekend, I wonder how many people who comment on it, will understand what it really means. The Cross and Resurrection of Christ cannot be reduced to historical/sociological theories that fit our preconceived narrative. Once you grasp that 'he is not here, he is risen, just as he said' (Matthew 28:6), the world is turned upside down and everything begins to make sense. The rest is theology!

David Robertson is the minister of Scots Kirk Presbyterian Church in Newcastle, New South Wales. He blogs at The Wee Flea.