Lynn, Harvey and Nyborg [Lynn, R., Harvey, J., & Nyborg, H. (in press). Average intelligence predicts atheism rates across 137 nations. "Doi:10.1016/j.intell.2008.03.004".] discovered that average intelligence (IQ) co-varies with national atheism rates. Extending this work, we investigated relationships among individual IQ scores, elementary cognitive task (ECT) performance, and three types of religious beliefs. Sectarianism (believing one's religion is the only path to God) correlated negatively with IQ and ECT. Considerable mean differences also existed on this factor between the highest and lowest IQ (d = 0.69) and ECT (d = 0.73) quartiles. Scriptural acceptance (believing one's scripture is literally true), however, correlated only nominally with IQ and ECT. Religious questioning (one's willingness to question religious convictions) correlated positively with ECT, and consistent differences existed on this factor between the highest and lowest scoring IQ (d = 0.38) and ECT (d = 0.55) quartiles. Only ECT explained unique variance in religious beliefs, as controlling for it attenuated the effects of IQ. Possible theoretical explanations for these effects are discussed. (Contains 3 tables.)