In the early 1970s, songwriter and guitarist Bob Hartman met bassist John DeGroff and formed the band Dove, which he quickly disbanded when DeGroff left to attend a Bible school in Fort Wayne, Indiana, known as the Christian Training Center. Hartman soon followed, and in 1972 he and DeGroff joined two classmates, guitarist Greg Hough and drummer Bill Glover, to form Petra. The band played small Midwest venues such as churches, coffeehouses and parks, to share the message of Christianity with concertgoers. Glover said on an interview "we weren't picky and we wanted to get God's Word out to our peers. We would set up in parking lots, parks, college campuses, coffee houses, etc." A frequent venue was a Fort Wayne Christian-themed coffeehouse named The Adam's Apple.