A 1,500-year-old 'gospel' may have been used as a spiritual guide to everyday problems, according to a researcher who has deciphered the text.

Written in Coptic, the language of ancient Egypt still used in the Coptic Church's liturgy today, the tiny book – only three inches high – was deciphered by Princeton papyrologist Anne Marie Luijendijk. It begins: "The Gospel of the lots of Mary, the mother of the Lord Jesus Christ, she to whom Gabriel the Archangel brought the good news. He who will go forward with his whole heart will obtain what he seeks. Only do not be of two minds."

In her book 'Forbidden Oracles? The Gospel of the Lots of Mary', Luijendijk says that she expected to find an account of the life of Jesus when she read the opening. However, the book consists of 37 vague 'oracles' which would have been used to help someone make decisions about a problem facing them, something like a newspaper horoscope.

For example, Oracle 34 reads, "Go forward immediately. This is a thing from God. You know that, behold, for many days you are suffering greatly. But it is of no concern to you, because you have come to the haven of victory."

Luijendijk said that the book's owner could have acted as a diviner, helping to interpret the oracles for people seeking an answer to a question – or it might have been for purely personal use. Its small size meant that it might have been designed to be concealed, as the Church discouraged such practices.

The 'gospel' is an example of a 'lot book', used in the ancient world to try to predict a person's future. According to Luijendijk, this is the only lot book found so far that calls itself a 'gospel'.

She told the LiveScience website: "The fact that this book is called that way is very significant. To me, it also really indicated that it had something to do [with] how people would consult it and also about being [seen] as good news.

"Nobody who wants to know the future wants to hear bad news in a sense."

The text is now owned by Harvard University's Sackler Museum. It was given to Harvard in 1984 by Beatrice Kelekian, who donated it in memory of her husband, Charles Dikran Kelekian. His father, Dikran Kelekian (1868-1951), was an influential trader of Coptic antiquaries.

It is not know how the Kelekians acquired the book, but Luijendijk believes it may have been used by a diviner at the Shrine of Saint Colluthus in Egypt, where archaeologists have found texts with written questions, indicating that the site was used for divination.