For many years, many theists and religious people have used some of the statements from Albert Einstein to demonstrate that he was a religious man, or that he believed in a personal God, or that he was ambivalent about belief in God, or that he was agnostic, and so on.
“God does not play dice with the universe”
For example, his famous quote, “God does not play dice with the universe” is wrongly interpreted as confession of his belief in God. One just cannot make such a direct conclusion. Many atheists refer to 'God' in their day-to-day speech. That does NOT necessarily mean they believe in a personal or religious God. The figure of speech using ‘God’ could mean differently in different contexts for different people, including atheists. But to conclude that Einstein was a believer from the above quotation is quite far fetched.
To understand why he said what he said, one has to know the context.
For eons, many cultures believed that God worked the laws of nature. (Biblical God has even created the nature with his hands, not necessarily abiding with laws of nature.) When Newton proposed Universal Theory of Gravitation thus setting the stage for Classical Physics, it was understood that the entire Universe was based on few well-understood laws of Physics making the universe and its workings deterministic.
That means, if you knew the position of a planet at this moment, and know its interactions with the environment, we can predict its position at any time in future. If there is an error in calculation, it’s only because all the factors in the environment that influence its behavior are not clearly stated. So, the problem is with the guy calculating the position of this planet, not with the universal laws of nature.
So, if we are not able to predict future, it’s only because we don’t have the complete knowledge of all the factors affecting that future. But theoretically, if we knew all the factors, we can predict the future absolutely without any error. That was the understanding under Classical Physics.
Then came Quantum Physics!
It told us that nature was NOT deterministic. That it was not possible to predict the future. That unpredictability and probability are inherent part of this Universe. That even if you knew all the factors in the environment absolutely, you would still NOT be able to predict the future. That the outcome of events is probabilistic! That the God played dice with universe!
Even Einstein, the greatest thinker of our time, could not reconcile himself to this reality. When he got to know how Quantum Physics worked, he could not believe it and uttered the now famous quote – ‘God does not play dice with Universe’.
Later on, with more understanding of this new and revolutionary physics, he has accepted Quantum Physics, and became a champion of it. He went onto accept that God does indeed play dice with the universe.
For him and everyone who knows the context, using God was a figure of speech. It does not speak of religion or belief in supernatural being who watches over us.
”Science without religion is lame”
Another famous quote which is often cited to say that Einstein approved of religion is – “Science without religion is lame, religion without science is blind.”
Many people used this quotation to say that religion was equally important to Einstein as much as Science. This philosophical and sociological statement only promotes harmony between the factions, but does not tell much about Einstein’s religious attitudes.
However, many religious people have used this quotation to prove that Einstein believed in God and that he approved of mainstream religion.
Then came the final quote to put an end to all this debate.
“God is nothing more than the expression and product of human weakness”
In a letter to philosopher Eric Gutkind, Einstein wrote: “The word god is for me nothing more than the expression and product of human weaknesses.”
And about Bible, he said: “[it is] a collection of honourable, but still primitive legends which are nevertheless pretty childish.”
About Judaism, he said: “For me the Jewish religion like all others is an incarnation of the most childish superstitions.”
About Jews, he said: “I cannot see anything 'chosen' about them.”
Einstein grew up in an environment where religion was extremely important. Though Einstein confessed that he ‘lost his religion’ at the age of 12, calling religion ‘a lie’, he remained slightly ambivalent when it came to the role of religion in society. His ideas on his personal god were closer to atheists, though he maintained respect for the necessity of religion.
His religion, if one can use that terminology, is captured more by his awe of the universe than the anthropomorphic God of the West or the human interventionist God of the East. To this effect, he said, “The most incomprehensible thing about the universe is its comprehensibility.”
But in no way he was a religious man as people describe their religions, and no way he was a believer in personal god as people define their gods.
At the same time, Einstein did not think he was an atheist. Some people categorize him as a deist - someone who does not believe in a personal god, or a religious god, but who believes that there is something more to this universe which is beyond human comprehension - but there is no room for miracles, prophecies or 'chosen people'.