Thanks to certain popular books, it's common to hear people say that the Bible can't be trusted because it's been changed. There are variations on this theme. Perhaps that Jesus was just a nice fellow but some naughty 'Christians' came along, made him into a god and fabricated what he said. Or that there isn't an original Bible, so how can you know what was originally said?

So what are we to say to this? Can we really trust the Bible's text?

1. There are differences between early manuscripts, but they help us to know what the original text said

If you have a modern Bible, you probably already have the evidence that the oldest manuscripts do have small differences between them. My New Living Translation (NLT), for example, puts notes on every Bible passage where there is a variation. Nearly always these are miniscule differences, such as Luke 4:1 – some manuscripts say 'in the wilderness" but others say "into the wilderness", which is hardly significant. This is because the Bible was originally transmitted by handwritten copyists, so small errors crept in. Most don't change the meaning and none have serious implications for doctrine.

Other differences are bigger: the oldest known manuscripts don't have John 8's story of the woman being stoned for adultery, and the ending of Mark is different. Why this is, and the implications of this, are discussed elsewhere and by academics at much length. Again, there is no difference that alters fundamental orthodox Christian doctrine – they refer to issues that are 'second order' or not central to the faith.

The practice of 'textual criticism' can use these different versions to trace back what the original text said, so these differences can actually lead to more confidence in the Bible, as some critics have acknowledged.

2. Christians are most concerned about what the original text means

Christians are happy to translate the Bible into different languages, and there are therefore many different translations. Scholars study the old manuscripts in Hebrew and Greek to make sure we understand what the original authors actually said. There may be different emphases in different translations and sometimes scholars disagree on what a text actually means. The NLT Bible, again, puts notes if there are other potential translations of the text: it is transparent.

If God wants to speak to us today through the Scriptures, wouldn't he want to do it in our own words? Languages change, could it be more important that ordinary Christians know the meaning of the Bible rather than the original language?

3. Those 'different Bibles'

It's often said that other gospels have been found that show a different Jesus, and so prove the Bible was changed. I often hear this attributed to the 'Dead Sea Scrolls', though this is a mistake as they are Jewish documents. Many of the manuscripts found in the Qumran cave were parts of the Old Testament – the oldest ever found.

In fact you could argue that discovering the Scrolls actually increased faith in Jesus, because they contained many copies of Isaiah, a Jewish book in the Old Testament that became particularly important for Christians. Isaiah 53, which so uncannily predicts the coming of Jesus and salvation through the Cross, had only one very minor difference to the Isaiah we already had when it was discovered. And this manuscript was written well before Christ was crucified, so it can't have been changed by Christians at a later date.

As to the Gnostic or 'alternative' gospels, well they're dated much later than the books of the New Testament. Common sense, and many scholars, says that they are therefore less reliable. They're very different in tone and substance to the Gospels. But evidence shows they were rarely used by the earliest Christians, as this table demonstrates, and so can't be said to reflect the original Church's beliefs.

4. Did the early Christians make up theology?

Another objection could be summarised thus: Jesus was a good man who taught a lot of nice things, but then later Christians came along and made up stuff about him being God. However, we know that most of the books of the New Testament were written within the first century: ie within 70 years of Jesus' death. And one of the earliest books is 1 Corinthians (which has that nice passage about love you always hear at weddings), which was written 20-30 years after Jesus' resurrection. This contains a very early creed, which said Jesus died for our sins and that he rose again: just the kind of beliefs sceptics normally say are invented. This very creed is believed to be even earlier than 1 Corinthians, because it has literary features that suggest it was said in Aramaic, the language Jesus and the disciples used.

5. Why would Christians change the Bible?

When faced with any version of this objection, it's worth asking: why would the early Christians have deliberately changed the Bible? What would have been their motivation?

In the modern world we often see Church as a concentration of power and money: both would provide motivations to manipulate religion.

However the earliest Christians who lived in the time of the earliest Biblical manuscripts that we have – that is the first three centuries of Christian history – had no ulterior motive to 'create Christianity'. They were being persecuted viciously for their faith but refused to respond with violence. They had no significant wealth or power. If anything, they would have been motivated to change the teachings to make their lives easier, so that they fitted more easily into their society, to stop the persecution or allow defence against their persecutors. Denying that Jesus was God and that he died for our sins would have saved them a lot of trouble.

Changing Jesus's teachings to avoid being non-violent, unselfish and unmaterialistic would have made their lives easier. But they didn't. Therefore, it makes much more sense to say that the fundamentals of what the Bible teaches haven't been changed.