The latest evidence given during an Australian sex abuse inquiry has revealed that children at a Christian school were repeatedly failed by authorities.

Emma Joy Fretton, now 34, testified on Friday. She told the royal commission that she was physically and sexually abused for more than four years at Northside Christian College in Melbourne. The abuse began when she was six years old.

Her abuser, teacher Kenneth Sandilands, was given a two year jail sentence in 2000 for offences against eight children at the school.

He received a second sentence in September 2014 for indecently assaulting underage pupils at St Paul's Anglican Primary School in Frankston, Victoria, in the 1970s.

As well as sexually abusing her, Fretton said Sandilands would write obscene stories about her family and force her to read them aloud "and agree they were true".

The abuse "destroyed her faith in the Lord," the commission heard.

Fretton testified that she reported the abuse to school officials, but was told "not to say anything to anyone". She was also assured that the school knew "what he is like" and that he would lose his job.

However, Sandilands remained Fretton's teacher for another two years.  Denis Smith, the senior pastor at the school, even faked a phone call to her mother. He told Fretton that her mother "couldn't make it" to a meeting about the abuse, when in reality she was never informed about it.

However, Smith's lawyer says pastor was not present at these meetings, the Guardian reports.

Also on Friday, Smith defended Sandilands' appointment, insisting: "I was being guided by the educators, the principal, because they would know what was right and what is wrong."

A teacher at the school, Margaret Furlong, also gave evidence. She told the commission that she reported three incidents of Sandilands' abuse to the school's principal, but was too "terrified and frightened" of Smith to take it further when nothing was done.

She referred to a "climate of fear" which may have stopped other teachers sharing concerns.

"From the very first day that I was employed at the college, we were told that the college was a ministry arm of the church, and we were under Pastor Smith and under God," she said.

"I didn't know what to do. I wish now that I had gone to the police."

"I put my trust in people that I thought would do the right thing – people I classed as Godly men," she added.

"These men did not do the right thing."

Northside Christian College is linked to Northside Christian Centre, now Encompass Church, in Victoria.

A statement from current pastor John Spinella said: "The criminal acts of Kenneth Sandilands robbed her [Fretton] and others of their innocence and trust. All things that children with the promise of life ahead of them are unquestionably entitled to.

"On behalf of Encompass Church, I acknowledge what happened to Emma and other victims of Kenneth Sandilands at Northside Christian College. I apologise to them for all past failings and the pain and suffering they endured."

The commission is examining how the Australian Christian Churches (ACC) movement, formerly Assemblies of God, handled allegations relating to Sandilands and two other men, including the 'Father' of Hillsong church, Frank Houston, who died in 2004.

The hearings will continue in Sydney until October 17.