Gregory Xavier Volz (born January 12, 1950 in Peoria, Illinois) is a Christian singer. He is most remembered for being the lead singer of legendary Christian rock band Petra from 1979 to 1985. Volz showed great skills in singing from a very early age. Being a self-taught musician, when he was 13 years old, he started his own band called The Wombats. As he grew up, he went on to share the stage with the likes of Janis Joplin, Chicago and others. In 1970 he became a born-again Christian and started performing with several Christian bands.