A 1954 letter in which Albert Einstein expressed his frank and critical thoughts on religion is once again going on the auction block ― and experts bet it could be sold for up to $1.5 million. The letter, Einstein’s blunt review of a contemporary Jewish philosopher’s book, offers insight into what the renowned physicist thought about God and his childhood faith as he approached the end of his life. “The word God is for me nothing more than the expression and product of human weaknesses, the Bible a collection of honorable, but still primitive legends which are nevertheless pretty childish,” Einstein wrote in German, according to a translation by The Guardian. The document, which is now known as “The God Letter,” is scheduled to be sold at Christie’s auction house in New York in early December.

Courtesy of Christies A photograph of "The God Letter," written by Albert Einstein to Eric Gutkind on Jan. 3, 1954. Christie's will put it up for auction in December.

Einstein was born into a secular Jewish family and stepped away from the dogma and doctrine of organized religion over time. His beliefs expanded into what he called a “cosmic religion” ― a way of approaching the universe and all its vast mysteries with an overwhelming sense of awe and a humble awareness of the limitations of the human mind. By 1954, one year before his death, he had completely rejected the idea of God and the beliefs of his childhood faith. Einstein expressed his views in a candid private letter to the Jewish philosopher Eric Gutkind, who had sent a copy of his book about intellectualism and Jewish spirituality, Choose Life: The Biblical Call to Revolt, to the physicist. Einstein wrote that while he had a deep admiration and love for the Jewish people, he had a much harder time accepting the Jewish faith. “For me the Jewish religion like all other religions is an incarnation of the most childish superstitions,” he wrote. “And the Jewish people to whom I gladly belong and with whose mentality I have a deep affinity have no different quality for me than all other people. As far as my experience goes, they are also no better than other human groups, although they are protected from the worst cancers by a lack of power.”

Sanford Roth via Getty Images Einstein, who was born into a secular Jewish family, came to embrace what he called a “cosmic religion” ― a way of approaching the universe with an overwhelming sense of awe and a humble awareness of the limitations of the human mind.