Students say Ronald Johnson's lively history lectures almost resemble "passionate sermons."

A former pastor, now a history professor at Texas State University in San Marcos, Texas, Johnson engages a roomful of undergrads as confidently as he preaches from the pulpit. During a recent lecture on "The South: Defense of Slavery,"the 42-year-old African-American-tall and lean, dressed in a tailored suit and tie-paced the classroom's center aisle, talking rapidly and gesturing energetically, jogging to students in different rows as they raised hands with questions.

Later, in a restaurant off-campus, Johnson nursed a cup of coffee while discussing his teaching experiences. The role of a Christian professor in a secular academic environment is multi-faceted, Johnson said, and he feels he's still growing into the job he loves. When asked how his faith impacts students, he hesitated: "I don't want to be seen as a model professor or Christian, a model anything." He referenced the cross hanging on his office wall as a symbol of the grace to which he credits every accomplishment.

Johnson grew up in a poor neighborhood in the small town of Lufkin, Texas, the youngest of nine children. His hardworking father cleaned yards and drove ammunition trucks during WWII, and his stay-at-home mother mixed water with canned chili and ketchup to make family meals stretch. Although his parents did not profess Christianity, they read the Bible and faithfully sent their children to Sunday school. He committed his life to Christ at 16.

One night in May 1989, Johnson's faith reignited after he fell asleep at the wheel and crashed into a concrete barrier at over 70 miles per hour. Shaken but unscathed, the 18-year-old drove on until his car died at a split in the road. He realized that "with not a scratch on me, my car all smashed up, God was offering a second chance." Johnson kneeled right there and prayed that if God got him home, he'd serve Him. He started back on foot, following the painted white line on Highway 103: "It was all I could see in the dark. I just walked the line. Like that Johnny Cash song," he said, laughing. Johnson kept walking until a couple drove by and offered to take him home.

Growing up, Johnson was an academically gifted honors student, teased for his straight-A grades in a neighborhood where knowing how to play basketball was more important than being literate. After he got accepted to Texas A&M,University Johnson learned his parents couldn't afford to send him, so he framed the acceptance letter over his bed "as a reminder that it wasn't going to stop me." And it didn't. Today, the first generation college graduate from rural East Texas has a B.A. in International Studies from Texas State University, an M.A. in American Foreign Policy from Johns Hopkins University, an M.Div. from Boston School of Theology, and a Ph.D in American History from Purdue University.

Johnson also served the Air Force chaplaincy and worked as a foreign service officer and CIA analyst. Other achievements include his upcoming book, Diplomacy in Black and White: John Adams, Toussaint Louverture, and Their Atlantic World Alliance. In the midst of his academic career, Johnson has also pastored several cross-cultural and African-American churches. He currently resides in Kyle, Texas, with his wife, Colette, and their two children.

In fall 2010, at the university's invitation, Johnson began teaching history at Texas State. During his first year, he downplayed his spiritual zeal, wanting acceptance as a "real" professor with intellectual depth. He kept faith references to a minimum until "I began to feel the clothes were not fitting. I decided to unball my spiritual fists and be me." Today, Johnson boldly shares his Christianity on a secular campus he says is friendly toward expressions of faith. The professor spoke with his trademark enthusiasm while describing how on the first day of class, he shows students a slide with a map of his hometown and emblems from his universities, the CIA, and the Air Force. In the center is the image of a cross: "I am a Christian," Johnson tells students. "Everything on that slide is because of the cross in the middle."

Also on the first day, Johnson assures the class he's praying for them. Students-and colleagues as well, some atheist and agnostic-regularly visit his office asking for prayer. Someone's parent may be diagnosed with cancer. Others are anxious, depressed or struggling to keep their faith. "In the secular university environment, students can be whoever they want for the first time, which is very confusing," Johnson said. "I ask God to show them who He wants them to be."

Melissa Babirad, a sophomore at Texas State, entered the university as a Christian still new in her faith. She recalls hearing Johnson quote Scripture and asking him to pray about her accepting a leadership role in her church. "He's really taught me a lot about discipling others," she said. Another former student of Johnson's, Ilana Hager, says Johnson is the only professor she's had who exemplifies a bold Christian witness on campus. During her difficult third semester, his encouragement gave her the "extra push" she needed to finish strong.

Johnson's background taught him to see Christian ministry as preaching, but he's since realized that "When I walk on campus, there's the harvest. There's my ministry." In his American history and religion classes, he creates a safe haven for intellectual exploration by encouraging students to share in class or email him if they're too afraid to speak publicly. His Christian students must make logical arguments based on both faith and reason, while non-Christian students learn to dialogue respectfully with believers without judgment or fear of being "changed."

As Johnson has shared freely-using biblical references in lectures or talking about his conversion-students have told him they feel more empowered to be themselves, too. Johnson hasn't received complaints about his Christianity, but stresses that he never uses his authority to evangelize or manipulate students. When referencing God in class, he always says, "the God I serve."

"Because I can't force them to serve Him, if they don't," he said. "My job is to respect them."

For Johnson, the image of the painted white line he followed as a teenager in 1989, walking home at night after his car accident, remains a metaphor for life. He says he's still "walking the line" today as a Christian professor at a secular university-stepping carefully but confidently in a spiritually dark environment with God and his conscience as a guide.

"The line between my worldview and the secular nature of the university is made visible by my view of higher learning," he said. "I do not see my role as instructor as telling students the answers, in class or about life. Education is a journey that can lead each of us to different places. What I can do is teach and live in a way that shines light on what God has done in my life."