The hard rock four-piece Creed was formed by two Florida high school friends, vocalist Scott Stapp and guitarist Mark Tremonti. The duo lost touch after graduation, but reunited in Tallahassee after Stapp underwent a few years of hard times. Stapp and Tremonti became Creed with the addition of bassist Brian Marshall and drummer Scott Phillips, with many of the group's lyrics obliquely addressing themes of Christian spirituality (Stapp's father was a Pentecostal minister). After being remixed for major-label release on Sony, the group's debut album, My Own Prison, did extremely well on the pop charts, selling over four million copies. Creed also scored four number one rock radio hits ("My Own Prison," "Torn," "What's This Life For," and "One"), making them the first band to accomplish the feat with their debut album. It was still charting in the Top 100 when the follow-up, Human Clay, was released in 1999. Human Clay debuted at number one, and its lead single "Higher" spent 17 weeks on top of the mainstream rock airplay charts. Human Clay went on to sell over six million copies, and had returned to the Top Ten a full year after its release, following the group's successful summer tour in 2000. That year, Marshall left the group to pursue other interests; Brett Hestla was named as his replacement for their US tour and the immediate future.