A new book says that the frescoes created by Michelangelo in the Sistine Chapel contained a secret code made up of mystical Jewish symbols, and insults aimed at the pope.

The ceiling of the Sistine Chapel, which the renaissance artist worked on for four years in the early 16th century, is actually a “bridge” between the Roman Catholic Church and the Jewish faith, according to The Sistine Secrets: Unlocking the Codes in Michelangelo’s Defiant Masterpiece, according to a report in British daily The Daily Telegraph.

The book is the work of Rabbi Benjamin Blech, an associate professor of Talmud at Yeshiva University in New York, and Roy Doliner, a tour guide at the Vatican.

Scanning through the arrangement of figures on the vast 14,000 square foot ceiling, the authors have found shapes that correspond to Hebrew letters.

For example, the book states, the figures of David and Goliath form the shape of the letter gimel, which symbolises g’vurah, or strength, in the mystical Kabbalah tradition. On the opposite wall, the scene showing Judith and her handmaiden carrying the head of the Assyrian general Holofernes is in the shape of the Hebrew letter ‘chet’, which represents chesed, or the characteristics of “loving kindness”.

“There are so many layers of meaning on meaning, and most of it is from the Jewish tradition,” said Doliner on an American television programme.

Rabbi Blech added that all the figures in the nine scenes on the ceiling are Jews.

“He emphasises only Old Testament figures in the entire ceiling, and what he was trying to say was: Why have we ignored our true roots?” he said.

The book adds that the tree of life in the fresco is not, as usually thought, an apple tree, but instead a fig tree according to ancient Jewish tradition.

The authors believe the entire Sistine Chapel, which they say is built to the same proportions as the Holy Temple in Jerusalem, is a “lost mystical message of universal love” which was intended to be decoded.

The authors believe Michelangelo picked up his knowledge of Judaism while at the court of Lorenzo de Medici in Florence.

In addition, they say there are several attacks on Pope Julius II, who commissioned the work, embedded in the painting.

Disgusted with papal corruption, they think Michelangelo painted the prophet Zechariah in the pope’s likeness. Behind him, one angel is “making an extremely obscene hand gesture at the back of his head.”

Critics of the new book point out that there is no record in Michelangelo’s writings of any secret code in the ceiling.