Thanks for the inquiry, Joan; it encouraged me to update this post with some new citation information, including links to the NY Times article where this was reported, and the original German of Einstein’s reply. Some added context can also be found here: https://www.google.com/books/edition/Einstein_on_Politics/7mmYDwAAQBAJ?hl=en&gbpv=1&bsq=%22spinoza%27s%20god%20who%20reveals%22