You don't have to read hundreds of books before you can discuss your faith with an atheist. Sometimes claims and questions that are just short soundbites can be answered just as quickly. At the London Evangelists' Conference yesterday, Professor John Lennox offered some quick responses to some common claims from atheists.

1) You don't believe in Zeus, Thor and all the other gods. I just go one god more than you, and reject the Christian God.

The problem with this idea is that 'gods' such as Zeus and Thor are not comparable with the biblical understanding of God.

"There is a vast distinction between all of the Ancient near eastern gods and the God of the Bible," said Prof Lennox. "They are products of the primeval mass and energy of the universe. The God of the Bible created the heavens and the earth".

2) Science has explained everything, and it doesn't include God.

Science cannot answer certain kinds of questions, such as 'what is ethical?' and 'what is beautiful?' Even when it comes to questions about the natural world, which science does explore and can sometimes answer, there are different types of explanations for different things.

"God no more competes with science as an explanation of the universe than Henry Ford competes with the law of internal combustion as an explanation of the motor car," says Prof Lennox.

3) Science is opposed to God.

There are certain conceptions of a 'god' that might be opposed to science, but not the Christian God. There might be certain kinds of 'gods' that are invented to explain things we don't understand, but they're not Christian.

"If we're being offered a choice between science and god... it is not a biblical concept of god," said Prof Lennox. "The biblical God is not a god of the gaps, but a God of the whole show. The bits we do understand [through science] and the bits we don't.

"Among many leading thinkers, their idea of god is thoroughly pagan. If you define god to be a god of the gaps, then you have got to offer a choice between science and god."

4) You can't prove that there is a God.

This kind of statement ignores that there are different kinds of 'proof'.

"Can you prove that there is a God?" asked Prof Lennox. "In the mathematical sense no, but proving anything is very difficult. The word proof has two meanings. There's the rigorous meaning in maths that is very difficult to do and rare. But then there's the other meaning – beyond reasonable doubt".

That's the kind of 'proof' we can present: arguments to bring someone beyond reasonable doubt. For example, rational arguments such as those from philosophers Alvin Plantinga and William Lane Craig, the personal experience of Christians, and the witness of the gospel accounts in the Bible.

5) Faith is believing without any evidence.

Christian belief has never been about having no evidence: the gospels were written to provide evidence, as the beginning of Luke's attests. The end of John's gospel says, "These are written that you may believe that Jesus is the Christ, the Son of God, and that believing you may have life in His name."

But believing without evidence is a common notion of 'faith' at present. "This definition is in the dictionary and believed by many," said Prof Lennox. "So, when we talk about faith in Christ, they think that's because there's no evidence. [John's gospel shows that] Christianity is an evidence-based faith."

6) Faith is a delusion. I'd no more believe in God than I would in the Easter Bunny, Father Christmas or the Flying Spaghetti Monster.

These ideas have been made famous by people such as Prof Richard Dawkins. The only thing they are good for is mockery.

"Statements by scientists are not always statements of science," said Prof Lennox. "Stephen Hawking said, "religion is a fairy story for people afraid of the dark". I said, "atheism is a fairy story for people afraid of the light".

"Neither of those statements proves anything at all. They're all reversible. What lies behind all these delusion claims is the Freudian idea of wish fulfilment [that we believe what we hope to be true.] This works brilliantly providing there is no god. But if there is a god, then atheism is wish fulfilment."

7) Christianity claims to be true, but there loads of denominations and they all disagree with each other, so it must be false.
Why does the existence of denominations imply Christianity is false? It might imply that Christians have very different personalities and cultures – or even that Christians aren't good at getting on with each other – but not that Christianity isn't true.

"There are all kinds of different kinds of teams in football, but they all play football," said Prof Lennox.

8) The Bible is immoral.

If you want to question the morality of the Bible, what basis does that morality have? There can be a serious contradiction within atheist criticisms. Dawkins wrote: "In a universe of electrons and selfish genes, blind physical forces and genetic replication, some people are going to get hurt, other people are going to get lucky, and you won't find any rhyme or reason in it, nor any justice. The universe that we observe has precisely the properties we should expect if there is, at bottom, no design, no purpose, no evil, no good, nothing but pitiless indifference."

If this is true, then why does he question the morality of anything? "Dawkins says faith is evil," said Prof Lennox. "But at the same time he abolishes the categories of good and evil. That doesn't make sense."

9) Surely you don't take the Bible literally?

Some atheists (and a few Christians) have a very black and white idea of how to interpret the Bible. You either have to take it 'literally' or chuck it away, they think. That ignores the reality of language and how it reflects truth.

"Jesus said 'I'm the door'," said Prof Lennox. "Is Jesus a door like a door over there? No. He is not a literal door, but he is a real door into a real experience of God. Metaphor stands for reality. The word 'literal' is useless."

10) What is the evidence for God?
You can debate the existence of God until the cows come home. It can be very interesting, especially when you go into the detail and explore the subject in depth. But for an atheist, they might be missing the point or avoiding the real issue. Prof Lennox advises to ask them the most important question:

"Suppose I could give [evidence for God], would you be prepared right now, to repent and trust Christ?"

Of course there are more in-depth answers to all of these claims – try out videos of debates between Prof Lennox and Prof Dawkins like this one: