Petra released Come and Join Us in 1977. Bob Hartman has said that this CD was a compromise, because they had to cut "Killing My Old Man" from the CD, and the record company wouldn't let them title the CD "God Gave Rock and Roll To You." The sound on this album is improved from their first one, and you can begin to see growth in the lyric-writing. On this album Petra continues to rock, moving away from the southern-rock to a sound more contemporary to the 70s. This album also features "Holy Ghost Power," which has a distinctly disco-style sound!