I'm not a Bible-believing Christian.

There, I've said it. On the other hand: I believe the Bible. And there's a difference.

Because 'Bible-believing Christian' has become not a harmless marker of a generous evangelicalism, but a slogan that increasingly defines hard-edged, ultra-conservative positions.

Here's a characterisation of the Bible-believing Christian that I'll try to keep on the right side of parody.

He or she is tough on gay rights and Muslims. Transgender people are wrong because Genesis says God made everyone male and female. Christians should be free to share their faith at work in any and all situations and should be allowed to discriminate against whomever they want. The penal substitutionary theory of the atonement is right. All non-Christians are going to hell forever. The world was created in six days a few thousand years ago.

It says so in the Bible, and if you don't believe these things you aren't a Bible-believing Christian.

Now, just to be clear: I'm not talking about the issues, I'm talking about the slogan and the way it's been hijacked. Because when you say you hold a particular view because you're a Bible-believing Christian, you say people who don't agree with you aren't. So you no longer have any common ground with them. You can't talk to them or reason with them. If they don't believe the Bible, they are no longer part of the tribe. You can't accommodate them in your denomination or group; you can't have them in your church pulpit; you don't acknowledge them as brothers or sisters in Christ, except, perhaps, in a purely theoretical sense. And this is a slogan that tends to be used by the theological right.

Now, it's obvious that some people don't believe the Bible – someone who doesn't believe in God, for instance. But we should be very, very careful about using that slogan about fellow-believers. The problem with it is that – like all slogans – it's lazy. It short-circuits real thinking. Because nine times out of 10, rather than condemning someone for not believing the Bible, we ought to be asking, "How does this person believe the Bible?"

And the answer is not always going to be straightforward, because the Bible itself never defines how we're to believe it. What it says is: "All Scripture is God-breathed and is useful for teaching, rebuking, correcting and training in righteousness." (2 Timothy 3:16) But the Bible was also written by human beings at particular points of history, for their own reasons. The precise relationship between the Spirit's inspiration and the human factor is not explained.

Does the the Bible intend to be scientifically accurate when it speaks of the Creation, or morally adequate when it talks about slavery? These things aren't self-evident. They have to be discussed. We need to establish a set of principles that will let us understand exactly what is going on when we say categorically: "the Bible says".

And if it's clear – and it is – that not every statement the Bible makes is to be taken as true in its literal and obvious reading, there is going to be legitimate room for debate about what particular parts of it actually mean.

That doesn't mean every part of it is up for grabs and that the Bible can mean whatever we want it to. One of the very human dangers we face in reading it is that we tend to explain away anything that's hard or unpalatable. We have to acknowledge that and beware of it.

Similarly, we should be guided by good scholarship. Most of us are not biblical scholars and we should defer to those who are. On the major doctrines of the Christian faith there is a consensus among scholars. Anyone who diverges from received wisdom on the Trinity, for instance, is probably not a Bible-believing Christian.

But at the same time, there needs to be among Christians a presumption of good faith. I'm profoundly unconvinced by some arguments about Scripture I've heard, on all sorts of subjects. But that doesn't mean I can say those who make them don't believe the Bible. They still revere it, they regard it as the word of God, but they interpret it differently. They too are Christians who believe the Bible.

Follow Mark Woods on Twitter: @RevMarkWoods