If you read just one Anne Frank comedy this year . . .

‘THERE SHOULD be a God, even though I know there probably isn’t. I’d like there to be – if he wasn’t the a*****e I was told about growing up.”

With those unminced words begins an hour of fascinating conversation with Shalom Auslander, whose first novel, Hope: A Tragedy, reflects his acerbic attitude. Such vehemence also provides an idea of where he stands, not just on religion, but on everything from family to politics and books. He doesn’t fence-sit, or do partisan, and his intensity is offset by how funny he is.

Auslander was born in 1970 to a strict Jewish Orthodox family in New York state. Religion was a fulcrum, and holidays, weekends and observing the Sabbath revolved around it. “Religion was everything, so I ran into a lot of hypocrisy. We spoke about God as an ever-present, malicious being and as ‘our father in heaven’; but my father on Earth was an a*****e, too.

“Here was a God who killed first-born sons, and we celebrate this every year? My image of God was a guy in his underwear, drunkenly stumbling around in heaven. And my dad was like that at home, so rejecting religion was about trying to get away from a father and mother – who were pretty s***ty – and become an individual.”

Auslander eventually wrote a memoir, Foreskin’s Lament, describing his mother as “the belle of the misery ball”. The book detailed his childhood unhappiness and the creeping doubt he felt about Jewishness. The two were initially inextricable, but hindsight and writing an unflinching memoir provided clarity.

“There was dysfunction in my family, and religion was almost an excuse. We just didn’t like each other very much. I stayed in contact with them for much longer than I should have, because of the idea of hope that’s in this book . . . the idea that families stay together and ultimately work out. None of the families in the Bible worked out, they’re all crazy.”

How does he feel about religion versus spirituality? “One thing I hate more than anything is certainty. I live in Woodstock. Being spiritual is about lighting incense and smoking a joint. It’s a cop-out word. I strive for atheism but I’m not quite there yet.

“In [Hope], the main character is someone who says they don’t want to believe in God, but couldn’t not believe. I’m closest to what has been termed ‘misatheist’ – someone who believes in God but hates him.” We are interrupted by Auslander’s seven-year-old son, who stops by the hotel lobby to give him a kiss. “Hey, buddy.”

The new book, Hope: A Tragedy, is Auslander’s first novel after his memoir and a short-story collection, Beware of God. Its protagonist, Kugel, is a married Jew trying to raise a young son while caring for his elderly mother. The family moves to a country farmhouse, only to discover that someone is living in the attic: Anne Frank (yes, that one). Instead of the martyred teen of Holocaust history, she is portrayed as an ill-tempered bag lady, bossy, malodorous and gripped by writer’s block as she attempts to write a novel.

A previous short story, God is a Big Happy Chicken, demonstrated Auslander’s exploration of irreverence, but did he fear people’s wrath by portraying Frank this way?

“My biggest concern is that it would become an ‘Anne Frank book’. It was never a case of me writing a book about Anne Frank, it’s me writing a book where I f**k with hope and ask: ‘What if hope is a bad thing?’”

Hope, when it comes to cancer diagnoses or sick children, is clearly contextual, and Auslander explains what he means. “I hoped for 10 very personal years that if I took my parents’ s**t they’d accept me. That was a bad thing. To me, Hope: A Tragedy isn’t a Jewish book. If I lived here [Ireland], I would have used the Famine.

“Aristotle said that man is the animal that laughs. Man is also the animal that came up with gas chambers, so what do I do, knowing that? Whether it’s Anne Frank or the Holocaust is irrelevant.”

In the book, Kugel’s mother-in-law, who was born in 1945, never experiences the death camps, but pretends that she has. This desire to be part of mass suffering also taps into a very modern proclivity for involving ourselves in public tragedy and global events, from the death of Princess Diana to 9/11.

Auslander has two young sons, and fatherhood looms thematically in his work. “To me, there is no story without Jonah [Kugel’s son]. Beckett didn’t have kids. I can say ‘I can’t go on, I’ll go on’, but I’m saying it with four kids in the back of the car on the way to a birthday party. My view of the world as a s****y place was formed in me by other people. Kugel goes through that too. It’s the idea of protection. If your child was going to die in an oven, why tell him?”

Like Jeanette Winterson, who struggled under evangelical parents, Auslander found solace in books. First, it was science and architecture (as possible careers and a way out, he admits) and later fiction, specifically Kafka, Vonnegut and Beckett.

It’s not difficult to see Beckett’s influence, particularly his edict that nothing is funnier than unhappiness. Auslander talks about discovering people “who were radical about death, existence, heartache and all the sacred cows”, from Voltaire and Monty Python to Bill Hicks.

“Mark Twain said that ‘Against the assault of laughter, nothing can stand’. When fascists come to power the first people they kill are the writers and the wits. You’ll know when fascism comes to America because they’ll kill Jon Stewart first.”

Auslander is not in touch with his family now, and has found a sense of peace. He opted to go into therapy when he met his wife, after feelings of happiness became tainted by guilt, and later suicidal thoughts.

“I had my suicide planned out. Some people are good at living, and I was not. It felt like being on a plane that was experiencing turbulence for 20 years, and I was bailing out. I also thought that it would be a huge ‘f**k you’ to God, because killing yourself is a huge sin.

“So I went to therapy, which made me realise that for the first 20 years of my life I had rolled lemons on the slot machines of life. When I met my wife and my shrink, I was rolling gold bars.

“Writing isn’t curative – it’s therapeutic. It’s like an Advil. It feels good when I take it, but it doesn’t mean the end of headaches. When a house is built with a bad foundation, it’s going to have scaffolding for the rest of its life. Writing gets me through it.”

Auslander prefers solitude, and after the current whirl of publicity he is keen to retreat from the world to work on his next book. I’ve heard it’s about sinning, I say. He smiles. “Always. I like sinning. I grew up with 600 commandments. If it doesn’t feel like a sin, I don’t want to do it.”

Hope: A Tragedy is published by Picador