A former Christian Brother labelled "satanic" for his sexual abuse of 20 boys will spend more time behind bars after a Victorian court increased his sentence.
Edward "Ted" Bales was handed a six-year jail term in March after he pleaded guilty to 34 child sex abuse offences which occurred in the 1970s and 1980s.
Prosecutors appealed, saying one of Bales' most heinous crimes against an 11-year-old boy warranted more jail time and his three-year non-parole period should be increased.
The Court of Appeal on Friday agreed, upping Bales' jail sentence to eight years and five months.
The non-parole period was increased to five years and eight months.
Bales abused the boy during a social visit to his family home, in his own bed when the boy's parents were in another room.
He whispered that his victim "would fail in life" because "God would punish" the boy for the acts.
The crime approached the worst kind of indecent assault, the court found.
"The breach of trust involved a betrayal of the responsibilities of (Bales) both as a teacher of the victim and as a member of the Christian Brothers order," the appeal judgment says.
Bales used his authority to prey on other victims, aged between eight and 14, at school.
Speaking outside court in March, one victim said Bales was "satanic" and an "evil monster".
Bales, formerly known as Edward Vernon Dowlan, changed his name to avoid being associated with other convicted pedophiles he taught alongside at the St Alipius school in Ballarat.
The 65-year-old was also jailed for historical child sex offences in the 1990s.
Bales has already served 344 days of his sentence.
