He developed his most marketable skill, comedy, as a youngster in church. ("Comedy is preaching," Foxx says.) That's also when he discovered music, learning dedication through piano lessons. Later, as the star quarterback at Terrell High School in Texas, Foxx learned the value of humility ("Learning not to be pompous, that was my whole thing," he says).
Now an Academy Award-winning actor, Grammy-nominated musician, film producer, radio host and standup comic, the 39-year-old entertainer still relies on those childhood lessons. He continues to follow the advice of a high school friend.
"He said you'll never be bigger than the game," Foxx recalls. "The game will always be here, even when we're gone and can't do it anymore. That's any business that we're in. ... You put the best you can into it and then whatever you get out of it, be humble and thankful."
On Foxx's gratitude list are his latest projects, which include a starring role in the action-thriller "The Kingdom," a weekly radio program on his own 24-hour channel on Sirius Satellite Radio, a follow-up to his hit R&B album and the occasional standup stint.
Comedy made him famous, but as a child, Foxx dreamed of being a singer.
"Before that I wanted to be a quarterback for the Dallas Cowboys," he says with a smile. "But when you find out you're not big enough, you've got to find something else to do."
At his grandmother's urging, Foxx started studying piano at age 5. He went on to play for various churches in his hometown and study classical music in college. Then he moved to Los Angeles to make it big.
When he didn't find success, he took a detour at the Comedy Store.
"I had some impressions up my sleeve," he says, suddenly talking like Mike Tyson, Ronald Reagan and Bill Cosby to prove the point. "That was my ticket. I said 'OK, I'm going to ride with this and I'm going to take the music and put it together with my jokes.' "
Thanks to a childhood spent in church, Foxx says he's "always been funny."
"Growing up in the country, church was where you got everything," he says. "It was where you got all your jokes, where you saw your first girl. Church, for me, was really the learning ground for everything."
In 1991, Foxx was plucked from the standup stage to join the cast of the sketch-comedy show "In Living Color," where he worked with Jim Carrey and "all 50,000 Wayans."
"I still pinch myself," Foxx says.
That led to "The Jamie Foxx Show" and eventually to his big-screen break: a leading part in Oliver Stone's football flick, "Any Given Sunday."
Six years later, Foxx won the best-actor Oscar (and practically every other acting prize) for his performance in "Ray."
He returned to music that same year, releasing his album, "Unpredictable," at the end of 2005. It earned four Grammy nods and won an American Music Award.
Despite starring roles in big-budget movies such as "Miami Vice" and "Dreamgirls," Foxx still keeps his hand in comedy. He pops into comedy clubs to do impromptu routines and keeps his colleagues laughing on movie sets.
"When Jamie is on, there's nothing more fun in the world," says Jennifer Garner, his co-star in "The Kingdom." "Nobody works, nothing gets done on set. Everybody stops to listen to Jamie do his bit."
"The Kingdom" director Peter Berg calls Foxx "a unique talent."
"He can do everything," Berg says. "He can do really funny one second and in the next second, turn gears and get very real. He's a complex guy."
Foxx says managing his multifaceted career requires particular vigilance. He wants to keep up the heat but not oversaturate the market: "That way you're not just all in people's hair." He carefully times the release of Jamie Foxx products. "The Kingdom" hits theaters Friday. His new album will be out next year. Then in 2009, he'll have "The Soloist," another film in which he plays a troubled musician.
Though music was his first love, Foxx says marketplace realities have made him change his tune about his favorite art: "After doing a record, it's not music anymore because the business is so crazy."
Now he has new appreciation for the freedom of comedy.
"The art of standup comedy is completely pure," he says. "It's you, a crowd, a microphone and your thoughts, just you observing life and letting people feel it."