doubtThe sociological data is clear: Christianity is on the decline in the United States.  The decline is not limited to one “type” of Christianity (though it is more drastic in some than others), nor is it limited to a particular race, gender, or age.  It is pervasive, but the most significant loss of faith is occurring in the Millennial generation.  Only 56% of Millennials identify as Christians.[1]  Larry Barnett of The Next Generation Project (TNGP) sought to discover the cause.[2]

Using three large representative data sources[3], he discovered that doubt is the major reason people are abandoning their Christian faith.  Christians who report having little or no doubt regarding the truth of Christianity are the most likely to be confessing Christians, regardless of age.  Millennial non-doubters are just as likely as all other generations of non-doubters to be confessing Christians.  Those who harbor significant doubts about the truth of Christianity, however, are more likely to abandon their Christian faith.  Age is a significant factor among the doubters, with Millennial doubters being much more likely to abandon Christianity than older Christians.

For example, 66% of Millennials who were raised in an Evangelical church but came to doubt the truth of the Bible abandoned their Christian faith.  Compare this to 43% of Baby Boomers who have done so, and 21% of the Silent Generation (born 1928-1945).  Older generations are more willing to harbor their doubts while remaining Christian than Millennials are.

A longitudinal study that questioned teens over a period of five years found that only ~10% of those Millennials who had previously reported no or few doubts came to abandon their Christian faith by the end of the study, whereas 20% of those teens who had reported some doubts and 39% of those who reported many doubts abandoned their Christian faith by the end of the study.  A high degree of intellectual doubt increases the likelihood that a Millennial will abandon their Christian faith in less than five years by 400%!

TNGP also found that doubt was corrosive to spiritual health (proportionate to the degree of doubt reported).  The more doubts people had, the less likely they were to pray, read the Bible, attend church, etc.

The data is clear.  When Millennials do not have doubts about the truth of their Christian faith they tend to remain Christian.  When they do have doubts, however, they are likely to abandon Christianity.  The spiritual health of doubters who are able to hold on to their Christian faith despite their doubts suffers greatly.  If the church wants to stop the bleeding of our young people abandoning the faith, we must educate them in Biblical theology and apologetics.  Mere moralizing, religious platitudes, entertainment, feel-good messages, and spiritualism is not enough.  They must know what they believe, why they believe it, and how we know it’s true.


[1]Pew Research Center, “America’s Changing Religious Landscape,” May 12, 2015; accessed 15 October 2015; available from
[2]The data presented in this blog post is taken from Larry Barnett’s article in Philosophia Christi.  See Larry Barnett, “The Need for Apologetics: What the Data Reveal about the Crisis of Faith among Young Christians in America” in Philosophia Christi. Vol. 17, No. 2, 2015 (473-487).
[3]The General Social Survey (University of Chicago, 60,000 interviews), the Religious Landscape Study (Pew Research Center, 35,000 interviews), and the National Study of Youth and Religion (University of North Carolina—Chapel Hill, longitudinal study).