Speaking of philosophy in the western tradition, the answer to the question will bring about other questions, namely , what is meant by the term "God"? For purposes of this post, I will use the Masonic meaning of the term, meaning a "supreme being." Starting with Thales, the first pre-Socratic philosopher we have on record, most philosophers prior to to Charles Darwin believed in a God of some sort, although what they meant by the term varied. There were skeptics along the way (Sextus Epicurus, Epicurus, Pyrrho, Lucretius, David Hume, etc), but they were not atheists in the way we use the term today, those who deny the existence of a supreme being. I mention Charles Darwin because as biologist Richard Dawkins said, he made it possible to be an "Intellectually fulfilled atheist." This is because before Darwin there was no other explanation as to why things looked so well designed in nature. While people like Hume did contend with the argument to design, even they had to admit there was still something out there that accounted for things, which you would call God.
Since Darwin, many philosophers have been atheists, agnostics, and non-theists, and depending upon which tradition you are in, that may be the dominant view. For instance, in analytic philosophy (the tradition I am in) I would say that there are more atheists, agnostics, and skeptics than theists. Not to say that some of our finest philosophers in this tradition have not been theists (Ludwig Wittgenstein), but the majority would be atheist leaning. It should be kept in mind though that while many in this tradition are not theists, most have no problem with others being theists in some since; Simon Blackburn (one of my favorite philosophers) said in a recent interview that he had lots of respect for religion, for instance.
|Ludwig Wittgenstein, a great philosopher who was open to faith|
In the continental tradition, where many of the universities are run by Catholics or other religions, there tends to be about a 50-50 split.
As to the second question about how philosophy has affected my own faith, I would say that it has strengthened it. For example, one of the top arguments against God is the problem of evil, but my knowledge of the pre-mortal existence make this a largely non-issue for me. Do not misunderstand, I often distress at the amount of pain and suffering in the world. However, I also know that to a certain extent I agreed to suffer before coming here, and I rejoiced at the opportunity. Also, I am aware that God is not obligated to make everything perfect for us on Earth; we are his children, not his pets.
On a second note, after reading Hume's Dialogues Concerning Natural Religion I was also rather convinced that God was immanent (involved in the world) rather than transcendent (beyond the world).
The Savior was once asked what the greatest commandment in the law was. He responded "Thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy mind. This is the first and great commandment." (Matthew 22:37-38) I see my study of philosophy and science as fulfilling the latter part of the commandment, to find God with my brain as well as with my heart.