His parents, Joseph and Sonya Smith, remained motionless as the two-week trial into their son's 2003 death ended.
The couple was found guilty of four counts of cruelty to children, three counts of aggravated assault, one count of reckless conduct and one count of false imprisonment in the death of their son, who was 8 when he died.
Sentencing was set for March 27.
The parents had been charged in a 14-count indictment in June with murder, cruelty to children, aggravated assault and false imprisonment in his death.
The Smiths were found not guilty of additional, separate counts of murder, felony murder, involuntary manslaughter, reckless conduct, false imprisonment and cruelty to children.
The Smiths are members of the Franklin, Tenn.-based Remnant Fellowship Church, which grew out of church leader Gwen Shamblin's Weigh Down Workshop, a faith-based diet program that she created in 1986.
Prosecutors charged that Josef was beaten by his parents, locked inside a wooden box and forced to stay inside a closet for hours at a time before he died in October 2003.
A police witness said Josef's father told officers his 8-year-old son frequently needed discipline because the child carved death threats on the walls that kept the family awake at night and claimed he was a foot-soldier for the devil.