'An hour's study of nature is worth a year's prayer.' - Prophet Mohammed
The full quote and more is here:
Belief in God a 'product of human weakness':Einstein letter
Just google in quotes ""the expression and product of human weaknesses", and you will get pages of hits
I guess Marx really wrote this:
"Religious distress is at the same time the expression of real distress and the protest against real distress. Religion is the sigh of the oppressed creature, the heart of a heartless world, just as it is the spirit of a spiritless situation. It is the opium of the people. The abolition of religion as the illusory happiness of the people is required for their real happiness. The demand to give up the illusion about its condition is the demand to give up a condition which needs illusions."
Karl Marx, Critique of Hegel’s Philosophy of Right
Seventy years under repressive, atheistic communism didn't succeed in stamping out the religion of the people in Russia.
1)The scientific achievements of Islamic culture were probably largely due the Muslim conquest and absorption of highly cultured and advanced civilizations (Persia and Byzantium) and contact with other sophisticated cultures (India and China).
2) Some have attributed the decline of Islamic civilization to aristocide perpetrated during the Mongol & Tartar conquests.
3) The letter dates from late in Einstein's life, long after his great achievements in physics.
4) While a genius in physics, Einstein showed no evidence of similar deep and original thinking regarding human culture, where his letter seems to be basically an echo of the rationalist, positivist, materialist ideas which dominated the intelligentsia in which he was reared.