As The Times reported in previewing the sale of the letter:

The God letter, written the year before Einstein’s death, seems to outline Einstein’s view of formal religion and the idea of a God who plays an active part in everyday life, answering individual prayers. “He did not believe in a God who went around choosing favorite sports teams or people,” Walter Isaacson, the author of the 2007 biography “Einstein,” said in an interview.

But at other times Einstein described himself as “not an atheist,” and the letter does not annul the seemingly spiritual characteristics of his thinking.

“Einstein often uses the word God — ‘God does not play dice with the universe,’” Rebecca Newberger Goldstein, who teaches philosophy and wrote “Plato at the Googleplex: Why Philosophy Won’t Go Away,” said in an interview. “A lot of physicists do this. It misleads people into thinking they’re theists, they believe in God. It’s a metaphorical way of talking about absolute truth. Einstein used it metaphorically and playfully.”

She said he had been religious when he was a child but “lost his religion and science took over.”

“Every time he was asked if he believe in God, he answered cagily: ‘I believe in Spinoza’s god,’” she said, referring to Baruch Spinoza, a 17th-century Dutch thinker who drew from Jewish religion and history. “If you say ‘I believe in Spinoza’s god,’ that’s already saying you don’t believe in what most people believe who believe in God believe. You believe the laws of nature are complete in themselves and contain all the answers.”

Gutkind had made the case in his book that “the Jewish soul is perfect intellectually as well as spiritually,” according to a review in Commentary magazine. “The mathematicized Einsteinian universe is Jewish as well as progressive, because it is anti-mythological.” Commentary also noted Gutkind’s “eagerness to find salvation for modern man in the Jewish spirit” (although the reviewer added that doing so induced Gutkind “to make the most extravagant claims in its behalf”).

Diana L. Kormos-Buchwald, a professor of history at the California Institute of Technology and the director of the Einstein Papers Project, said that Einstein was “not particularly thrilled at the special place that Gutkind devotes to Einstein’s science as the — how shall we put it — the best example of Jewish deterministic thought.”

“The Jews are the only group to which he feels he could belong,” she said. “But he identifies with them because that is what he was born into, not because they are the chosen people.”

She summarized the letter as “a nice way” to tell Gutkind, “I don’t think like you and I don’t like what you’re saying.” She said that Gutkind’s book had mentioned Einstein 11 times “and holds up Einsteinian physics as the new overarching philosophy of the universe, of space and time.”