College-aged millennials today are far more likely than the general population to be religiously unaffiliated. This is true when they are compared to previous generations as well.
In fact, the Pew Research Center documents that millennials are the least outwardly religious American generation, where “one in four are unaffiliated with any religion, far more than the share of older adults when they were ages 18 to 29.”
Just over 60 percent of millennials say that Christianity is “judgmental,” and 64 percent say that “anti-gay” best describes most churches today.
In ministry circles, it has long been reported that of youth raised in homes that were to some degree “Christian,” roughly three-quarters will jettison that faith after high school. Just under half of this number will return to some level of church involvement in their late 20s or early 30s. 
It has long been recognized that experience with an earthly father deeply informs the perspective about the heavenly father. In “How the West Really Lost God,” sociologist Mary Eberstadt correctly asserts, “The fortunes of religion rise or fall with the state of the family.”
Why is this? Our most recent research, which includes dozens of interviews with teens, twentysomethings, professed ex-Christians, and religion and culture experts, points to factors like these:
1. Mindset of “digital natives” is very much separate from other generations. Millennials are eclectic on all fronts—economically, spiritually, artistically. There is little or no “brand loyalty” in most areas of life.
2. Breakdown of the family. It has long been recognized that experience with an earthly father deeply informs the perspective about the heavenly father. In “How the West Really Lost God, sociologist Mary Eberstadt correctly asserts, “The fortunes of religion rise or fall with the state of the family.”
3. Militant secularism: Embraced by media and enforced in schools, secular education approaches learning through the lens of “methodological naturalism.” It is presupposed that all faith claims are merely expressions of subjective preference. The only “true” truths are claims that are divorced from any supernatural context and impose no moral obligations on human behavior. People today are subjected to an enforced secularism.
4. Lack of spiritual authenticity among adults. Many youth have had no -- or very limited -- exposure to adult role models who know what they believe, why they believe it, and are committed to consistently living it out.
5. The church’s cultural influence has diminished. The little neighborhood church is often assumed to be irrelevant, and there is no cultural guilt anymore for those who abandon involvement.
6. Pervasive cultural abandonment of morality. The idea of objective moral truth—ethical norms that really are binding on all people—is unknown to most and is rejected by the rest.
7. Intellectual skepticism. College students are encouraged to accept platitudes like “life is about asking questions, not about dogmatic answers.” Is that the answer? That there are no answers? Claiming to have answers is viewed as “impolite.” On life’s ultimate questions, it is much more socially acceptable to “suspend judgment.”
8. The rise of a fad called “atheism.” Full of self-congratulatory swagger and blasphemous bravado, pop-level atheists such as the late Christopher Hitchens (whom I interviewed twice) made it cool to be a non-believer. Many millennials, though mostly 20-something Caucasian males, are enamored by books and blogs run by God-hating “thinkers.”
9.  Our new God: Tolerance be Thy name. “Tolerance” today essentially means, “Because my truth is, well, my truth, no one may ever question any behavior or belief I hold.” This “standard” has become so ingrained that it is now impossible to rationally critique any belief or behavior without a backlash of criticism.
10. The commonly defiant posture of young adulthood. As we leave adolescence and morph into adulthood, we all can be susceptible to an inflated sense of our own intelligence and giftedness. During the late teens and early 20s, many young people feel 10 feet tall and bulletproof. I did. The cultural trend toward rejection of God—and other loci of authority—resonates strongly with the desire for autonomy felt in young adulthood.
Finally, is it really any wonder that kids raised in the churches of 21st century America aren’t often stirred to lifelong commitment? Most churches are so occupied with “marketing” themselves to prospective attendees that they wouldn’t dream of risking their “brand” by speaking tough-as-nails truth.
For evangelical youth mentored by many a hip and zany “Minister to Students,” commitment to Jesus lasts about as long as the time it takes to wash the stains out of T-shirts worn at the senior-year paintball retreat.
It is true that our culture has grown visibly antithetical to God and Christian commitment. But in addressing the spiritual attrition rate of young America, it must be admitted that a prayerless, powerless church peddling versions of “Christianity Lite” share in the blame. God only knows the degree of our complicity, and also the time when we’ll be concerned enough to change direction.
Dr. Alex McFarland is Director for Christian Worldview and Apologetics at North Greenville University. His latest book is “Abandoned Faith: Why Millennials Are Walking Away and How You Can Lead Them Home.” 
Source: http://www.foxnews.com/opinion/2017/04/30/ten-reasons-millennials-are-backing-away-from-god-and-christianity.html