"Some of the greatest scientists, such as Albert Einstein and Stephen Hawking, are devout Christians. They understand that science alone is not sufficient to explain the universe. If men like that can see it, then why can't you?"

Creationists love to pretend that great scientists are or were "devout Christians". They distort peoples' words in order to pretend that deists or atheists (such as most scientists and many of the American "founding fathers") are or were Christian, or that bad Christians (eg. Adolf Hitler) were actually pagans or atheists.

Colloquial English is strewn with language that makes reference to God, and if you wanted to, I'm sure you could make it appear as if anyone is a "devout Christian", including me. I am an atheist, yet I routinely use exclamations such as "Jesus Christ!" or "Thank God", because phrases like that have simply entered the vernacular. I've made reference to Hell countless times, and in various discussions I've even made reference to the useful aspects of religion on occasion (usually with respect to its power as an instrument of social control, but it wouldn't be hard to take my quotes out of context to change their implication). I've attended church services in the past, and I've politely bowed my head so as not to offend Christians who were saying grace at the dinner table. It would quite frankly be child's play to take phrases and pictures from my life to convince someone that I'm a Christian, even though nothing could be further from the truth. Something to keep in mind whenever you hear a single sentence being used as proof of someone's religiosity.

As for Einstein himself, he spoke of God and of religion, but it was a religion and a God of his own making (a sort of "cosmic religion" of science, as he called it), and it bore no resemblance whatsoever to the Christian God. From his Autobiographical Notes:

Hear that? Albert Einstein says that science showed that the Bible could not be true. And in response to a child who asked if scientists pray, he wrote:

Does this sound like a man who believes in Genesis, Original Sin, Jesus Christ, and the Ten Commandments? Albert Einstein was a free thinker and a deist, not a Christian. As for Stephen Hawking, he often makes reference to God. But which God does he believe in? The Christian God, or Einstein's God? Does he believe in miracles, the Second Coming, Jesus Christ, and creationism, or does he believe in an impersonal deity who created the laws of the universe but does not interfere in its operation? It would be good to examine his words in more detail, rather than simply noting that he often uses the word "God". When discussing the laws of physics, he said (from "A Brief History of Time"):

It's quite obvious that Stephen Hawking, like Albert Einstein, does not believe in the Bible. The "gods" of such men do not make miracles, interfere in the affairs of men, watch over us, or offer punishment and reward for our allegiance. Creationists appeal to the authority of Albert Einstein and Stephen Hawking because they think they can use it to win an argument, not because there's any truth to their claims.

Fallacy watch:

• Appeal to Authority (assumes that if Einstein said it, then it must be true, which in turn implies that Einstein was infallible; Einstein was a genius but he was not infallible).
  
• Misrepresentation (technically not a fallacy, since it falls into the category of outright lies rather than logic fallacies, but it is certainly a dishonest debate tactic to say that Einstein and Hawking believed things they did not actually believe).