A 2003 Harris poll found that 90 percent of American adults believe in God, and that most also believe in heaven and hell (82 percent and 69 percent, respectively). More recently, a 2018 Pew Study found that 56 percent of Americans believe in “God as described in the Bible,” one-third believed in some other kind of God or higher power, and 10 percent had no such spiritual belief at all. Many believe that God protects them (77 percent), has rewarded them (67 percent), has punished them (40 percent), or talks to them (28 percent).
Does all this belief change anyone's behavior? Perhaps not. It certainly drives religious behavior: In 2014, Pew found that 36 percent of Americans claimed to attend religious services at least once a week, while 30 percent never (or almost never) go at all. Personal belief and identity also drive the amount that people donate to congregations, religious charities, and religiously-branded charities. Outside of religious activity, however, the impact of belief on the rest of life is debatable. In 2011, The Week reported that a newly released study from Kansas University "found almost no difference in the sex practices of atheists and highly religious people, except that the religious felt very guilty..." And in 2013, a small study revealed how criminals use religion to justify their crimes:
"The authors surveyed 48 'hardcore street offenders' in and around Atlanta, in hopes of determining what effect, if any, religion has on their behavior. While the vast majority of those surveyed (45 out of 48 people) claimed to be religious, the authors found that the interviewees 'seemed to go out of their way to reconcile their belief in God with their serious predatory offending. They frequently employed elaborate and creative rationalizations in the process and actively exploit religious doctrine to justify their crimes.'"
Beliefs in Europe vary widely, with a 2005 survey (cited by Barbara King) showing that 97 percent in Poland and 37 percent in the Czech Republic saying they believe in God. That survey included 14 countries. It is not clear whether Denmark and Sweden were on the list, but of those nations, Victor Stenger once noted that "about 20 percent believe in a personal God, consider God to be important in their lives, and believe in life after death..."
On any local level, beliefs may be slow to change, in part because, as George Cunningham put it, "There is a 7 in 10 chance that you have the same religious affiliation as your parents."
Scientists are far more likely to to be atheists than the rest of the population. A 2007 survey of 1,646 scientists conducted by Ecklund and Scheitle found 62 percent atheist or agnostic, while 10 percent were certain of God's existence and 4 percent believed that "there is the most truth in one religion." A 2009 Pew study found that approximately half of U.S. scientists believed in God or a higher power, while the other half did not or would not say. A 2005 study found that natural scientists are more likely than social scientists to be atheists.
2003 Harris poll cited in Barbara J. King. Evolving God: A Provocative View on the Origins of Religion. New York: Doubleday, 2007. p. 220.
The Week, June 10, 2011, p. 6.
Victor J. Stenger. The New Atheism: Taking a Stand for Science and Reason. Amherst, N.Y.: Prometheus Books, 2009. p. 234.
Cited in Barbara J. King. Evolving God: A Provocative View on the Origins of Religion. New York: Doubleday, 2007. p. 228.
George C. Cunningham. Decoding the Language of God: Can a Scientist Really Be a Believer? Prometheus Books, 2009. p. 80.
Survey results of Elaine Howard Ecklund and Christopher Scheitle funded by the Templeton Foundation and published in 2007. Cited in George C. Cunningham. Decoding the Language of God: Can a Scientist Really Be a Believer? Prometheus Books, 2009. p. 18.