In a nationwide survey of Americans, the Barna Research Group found that 58% do not know who preached the Sermon on the Mount. Most Americans cannot identify the names of the first four books of the New Testament. Half of all adults (52%) did not know that the book of Jonah is in the Bible. Half of all adults (48%) did not know that the book of Thomas is not in the Bible. Seven out of ten adults did not know that the expression “God helps those that help themselves” is not contained within the Bible.

Quoted in Why Christians Sin, J. Kirk Johnston, Discovery House, 1992, p. 68