One commands mankind to be fruitful and multiply. The other shows us how to do it. The Bible and the Kama Sutra do not immediately have much in common.
The first provides the western world with a spiritual and moral code. The second, with its complex series of sexual positions, is an Indian guide to the pleasures of the flesh.
But these two texts appear in a list of must-read books compiled by librarians around the country. In a survey conducted to coincide with last week's World Book Day, librarians were asked which books everyone should read before they died.
First place was taken by classroom classic, To Kill a Mockingbird, Harper Lee's tale of racism in the deep south. The Bible was second, followed by classic novels, such as Jane Eyre and David Copperfield. The only other ancient text to appear on the list was the Kama Sutra.
Louise de Winter, director of the Museums, Libraries and Archives Council, which conducted the survey, said: "All books provide lessons for life. To Kill a Mockingbird was written for children, but it tackles difficult issues. It's a grown-up book as well.
"Possibly what makes these books classics is that children and grown-ups take different things from them."
Ancient texts, she said, have particular appeal: "The Bible is packed with cracking great stories. It is the basis of so much literature even now. And the Kama Sutra - I suppose there are certain things adults need to know, and it is a pretty comprehensive guide. It also shows librarians have moved on a bit from the buttoned-cardigan image."
Helen Emery, librarian at King Edward VI comprehensive in Staffordshire, agrees that studying ancient texts is important.
"The Bible is such a fundamental text in terms of world religions," she said. "Reading it is important for tolerance and understanding.
"I'm all for cultural awareness. If a student says, I'm interested in the Kama Sutra, you can't censor them. You need to consider their level and get parental permission. But if they can cope with it, you should encourage people's interests."
But Ian McNeilly, of the National Association for the Teaching of English, does not anticipate schools using the Kama Sutra as a set text.
"I'm sure adolescent boys would find it very interesting," he said. "But I can't see them engaging with the text. They'd get distracted by the nature of the images."