On Descartes,
But let's go to Descartes, shall we? In Principles of Philosophy, he writes,He had a deep religious faith as a Roman Catholic, which he retained to his dying day
This is clearly not the Christian God. God manifested on earth in the form of Jesus Christ, who, according to Christianity, was a living, breathing, sensing (divine) human. Descartes does not attribute reason to his God - throughout his work, he distinguishes reason (intelligence drawn from the senses) from the will and wisdom. To Descartes, the laws and output of emergent processes (including, in my opinion, his vague notion of evolution) were "God." Of course, if he didn't use the term God, he would have been quickly censored (most likely murdered).The nature of body includes divisibility along with extension in space, and since being divisible is an imperfection, it is certain that God is not a body. Again, the fact that we perceive through the senses is for us a perfection of a kind; but all sense-perception involves being acted upon, and to be acted upon is to be dependent on something else. Hence it cannot in any way be supposed that God perceives by means of the senses, but only that he understands and wills. And even his understanding and willing does not happen, in our case, by means of operation that are in a certain sense distinct one from another; we must rather suppose that there is always a single identical and perfectly simple act by means of which he simultaneously understands, wills, and accomplishes everything.
In Discourse on the Method, Descartes writes,
Essentially he argues that no matter what God did, these physical laws would exist. They don't come from God, they exist independent of God.From that I went on to speak of the earth in particular: how, although I had expressly supposed that God had put no gravity into the matter of which it was formed, still all its parts tended exactly toward its centre; how, there being water and air on its surface, the disposition of the heavens and heavenly bodies (chiefly the moon), had to cause an ebb and flow similar in all respects to that observed in our seas
Of course, he later writes,
Why do you think, after explaining in detail how much of the functioning of the universe can be explained without God, he suddenly says "This probably isn't how it happened!" He didn't want to be killed for his beliefs.Yet I did not wish to infer from all this that our world was created in the way I proposed, for it is much more likely that from the beginning God made it just as it had to be.
Look at this (still the same page):
Sounds a whole lot like evolution.So, even if in the beginning God had given the world only the form of a chaos, provided that he established the laws of nature and then lent his concurrence to enable nature to operate as it normally does, we may believe without impugning the miracle of creation that by this means alone all purely material things could in the course of time have come to be just as we now see them. And their nature is much easier to conceive if we see them develop gradually in this way than if we consider them only in their completed form.
As for Einstein, I'll let him speak for himself (you only chose to quote part of what he said!):
It was, of course, a lie what you read about my religious convictions, a lie which is being systematically repeated. I do not believe in a personal God and I have never denied this but have expressed it clearly. If something is in me which can be called religious then it is the unbounded admiration for the structure of the world so far as our science can reveal it.