Complex sentence: Thibodeaux returned to the southern United States, where he and his wife settled in Jackson Mississippi; in 1979 to rejoin the band David and the Giants only to learn that the other band members had also become Christians.
Split into simpler sentences: Thibodeaux returned to the southern United States in 1979, where he and his wife settled in Jackson Mississippi. In 1979 Thibodeaux decided to return to his band David and the Giants only to learn that the other band members had also become Christians.