On his 'Real Time' talk show on Saturday, American comedian Bill Maher called God a "psychotic mass murderer" because of what God does in the account of the flood in Genesis.

Speaking in relation to the new film Noah, Mr Maher was quoted in the Washington Times as saying: "Hey God, you know you're kind of a [expletive] when you're in a movie with Russell Crowe and you're the one with anger issues.

"Conservatives are always going on about how Americans are losing their values and their morality, well maybe it's because you worship a guy who drowns babies."

To answer whether this is a fair response to what happens in that account, Christian Today talked to Reverend David Robertson of St Peter's Free Church in Dundee.

Rev Robertson is a noted Christian Apologist, and is the author of "The Dawkins Letters", a response to the objections to Christianity raised by Richard Dawkins and the so-called 'New Atheists'.

Here's what he had to say.

CT: Mr Maher's assertion is a common one - that God's actions in the flood, killing everyone on earth except Noah and his extended family, are in fact evil and could even be called genocidal.

DR: Well, I would answer that in several ways. First, I would ask the basis on which they are making that judgement. They are presupposing within that the existence of a right and a wrong extending back across many centuries, and I would just ask what they base that right and wrong on.

I would applaud their motivation in acknowledging that there is an absolute right and wrong, but without God, there really can't be that kind of absolute morality that they're basing their judgement on.

Secondly, in terms of what actually happened, people have to read the whole story in context. Remember, everyone dies. Everyone in our day is going to die, everyone in Noah's day was going to die.

If there is an almighty God, and he has ultimate control over who lives and who dies, then it's not like a human being who goes out and commits genocide. God doesn't commit genocide.

People are going to die anyway, so would there be a reason for God to allow such a spectacular event to happen at that time? An event which would prevent the human race from going down the path it was going down. I think there was.

The whole world was destroying itself. Humanity was killing both itself and God's world. What if the best option was to start again?

I would say that most people when they ask the question about whether the flood was somehow evil, they're thinking 'what about all these innocent people and this wonderful word? How could God come along and just arbitrarily remove them?'

But what if it wasn't arbitrary. What if it was actual justice? Are we in a position to say that it wasn't?

The truth is, we're not in a position to judge God. I think that as a Christian I accept that what God does is right and just and fair, and I look at the account of Noah and I say 'Wow, was the world in that much of a mess?' Sometimes I look at the world today and I can see how it was.

CT: What would you say to people who, upon hearing that answer, would then say 'surely that means God can just do whatever he wants?'

DR: God can do whatever he wants, that's actually correct. But what God wants will always be just and will always be good. The notion of God as capricious, as someone whose playing some kind of giant game of The Sims, that doesn't work.

God only acts in accordance with his own nature. God cannot lie, for example. God still does whatever he wants because God doesn't want to lie.

Again, I would ask where this question is coming from. Does the person asking this think that human beings can do whatever they want?

The idea of human autonomy is incredibly appealing these days, the idea that 'I can do what I want, as long as I don't harm others'. I would say to that 'who defines what harm is?'

There are some things that we will do that will harm others, and how do we decide when that's right and when that's wrong?

So yes, God does do whatever he wants, but Christians have faith in a God who wants to do what is right and what is good, and in fact can't do anything bad because of his nature.

I would say that we don't really have the right to project onto God our perceptions of what is right and wrong, which actually are derived from God's ultimate standard of good anyway, but filtered through our own weaknesses and flaws.

I'd start it from the opposite end. Breaking it down into three points we can say that:

1. God can do whatever he wants.
2. What God wants is good.
3. If I look at a particular action of God's and ask 'how can that be good?' that's a good question, but I don't have the right to say 'well this is bad, and therefore God is bad' or 'God doesn't exist'.

I think to live in a world in which God was not good, or there was no good, in the way that someone like Richard Dawkins believes, would be hell.

I think what God did in the flood was to preserve the earth. There's plenty of people who ask this kind of question who talk about global warming and natural disasters and Gaia or Mother Earth taking revenge and wiping out human beings for the damage they cause and they don't see any problem with that.

In the same way, I don't see any problem with an almighty God protecting his earth and deciding to restart humanity through a flood.

CT: If you were talking to a Non-Christian about the flood, what kind of lessons about God would you want them to take away from it?

DR: The interesting things that we can learn from the story is looking back to how the early Church used the story, and how they believed that the ark was like the Church.

For me, Noah being a priest of righteousness in a corrupt generation is important. God didn't just randomly choose Noah and said to him 'right, you're saved'. Noah was someone who preached righteousness. If people had believed, they would have been saved too.

The message I would use about the flood, in terms of the Gospel, is to say that the world is screwed up, we are screwed up. Whether it's global warming or whatever catastrophe is coming, we are all faced with death, that's something we all have in common.

In response to that, I would say that God has sent the ultimate preacher of righteousness and the ultimate ark, and that is Jesus Christ.