Tasmanian Justice Gregory Geason struck the woman at a Hobart home in October 2023 and pushed her, causing her to fall into a mantelpiece and suffer concussion and bruising,
He was found guilty on October 16 of assault and one count of emotional abuse or intimidation, which involved tracking her movements, being jealous, aggressive and calling her names.
During sentencing submissions on Tuesday, Geason's lawyer Fabiano Cangelosi told Hobart Magistrates Court his client would resign as a Supreme Court judge.
"(Geason) considers he has lost the moral authority necessary for any judicial officer to sit in judgment over other human beings," Mr Canglosi said.
"The defendant has reached the conclusion he is not able to sit as a judge."
Tasmania's parliament in December abandoned an attempt to suspend Geason, who has been on leave since November 2023, because of constitutional worries.
No date was aired in court for the resignation of Geason, 63, who is expected to be sentenced on Thursday.
Mr Cangelosi said there was an acceptance parliament would likely try to remove Geason following the guilty ruling and recent law reforms.
Mr Cangelosi said Geason, who had given a written undertaking to not serve as a judge until the conclusion of criminal proceedings, had "lost everything".
"The destruction of his public image and professional life is total," Mr Cangelosi said.
The maximum penalties for common assault were 12 months jail and a $4040 fine, while emotional abuse carried a maximum two-year jail term and $8080 fine, the court was told.
Mr Cangelosi said Geason posed "practically" no risk of reoffending and the crimes were out of character.
"He loved (her). There remains clear evidence of his support for her during the relationship, in an emotional sense and a material sense," he said.
Director of public prosecutions Daryl Coates SC said Geason's offending was a serious example of common assault.
He said the assault stemmed from jealousy, a desire to control the woman and contained numerous applications of force resulting in extensive bruising and a concussion.
Mr Coates said a jail term, suspended or not, should be considered.
In a statement read to the court via video link, the woman said she was in hospital for months, couldn't work for eight months and was no longer the same person.
She said she had become a recluse, set up video cameras around her home and was constantly looking over her shoulder.
"How could someone I loved and respected … do this to me?," she said.
Magistrate Susan Wakeling previously found the woman, who gave evidence at a week-plus hearing, to be a truthful witness.
Ms Wakeling said Geason's version of the assault, in which he said the woman fell, was "contrived and implausible".
Geason pleaded guilty in a NSW court on November 8 to breaching a family violence order and is expected to be sentenced in December.
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