A former Adelaide real estate director and pastor strayed far from the teachings of Christ when he deceitfully fleeced people out of investment money, a judge says.

David Owen Parkinson, 63, has pleaded guilty to 59 fraud and deception charges over a four-year period and faced the District Court for sentencing submissions on Monday.

Defence lawyer Nick Vadasz said Parkinson was from a “deeply religious” background and his offences “touched on his hopes and aims”.

“They were not committed by someone who was preying on people in church,” Mr Vadasz said.

“He believed that he was helping others. Even now he believes he can repay and make good the losses.”

But Judge Jack Costello wasn’t buying the argument, saying Parkinson’s dozens of victims were betrayed.

“Is that supposed to make the offences seem less heinous?” the judge said.

“He has betrayed the trust of those who trusted him the most.

“He’s a man who has studied the teachings of Christ to the point of becoming a minister.

“For someone with the religious credentials, he’s certainly departed from the tenets of Christ in a sustained and completely deceitful manner.”

Parkinson was working at Ray White Real Estate in North Adelaide and was also a church minister when he committed the offences between 2009 and 2012.

Prosecutor Will Ellis said he left his victims more than $800,000 out of pocket through his investment scams and Ponzi schemes, and said Parkinson deserved a prison sentence.

“On many occasions Mr Parkinson used church connections. Many of the victims came to him as a friend,” Mr Ellis said.

“Many of them were highly vulnerable and he ruthlessly encouraged them to take out mortgages.”

Parkinson was born in New Zealand, where he started his finance career, before coming to Australia, living in Queensland then South Australia.

He flew with his wife to India in 2014 but he was arrested at Adelaide Airport upon return to Australia in 2015 and has been in prison since.

Judge Costello ordered a home detention suitability report. Parkinson will return to court on April 7.