Erikson crashed a May 2019 service at Metropolitan Community Church in Hawthorn with two women, live-streaming the ordeal to his followers online.
A few minutes after a bible discussion began, Erikson got up from his seat and, while standing in front of about 20 parishioners, asked: "Does your church marry Sodomites?"
He then hurled further abuse, including "you're not Christians you're a bunch of "fa***ts".
Reverend Susan Townsend asked him to leave, with other parishioners standing up behind her and walking towards Erikson.
"To have somebody come in and directly offend members of the church, it was disgusting," she told Melbourne's County Court on Tuesday.
Erikson was found guilty of disturbing a religious service and sentenced to 10 weeks' jail in July 2021, but he has launched an appeal against his conviction and sentence.
Rev Townsend, who gave evidence to the appeal, said when Erikson refused to leave the church parishioners surrounded him and forced him out into the hallway.
"He said he read on our website that all are welcome, to which I said 'well you're not welcome because your behaviour is inappropriate'," she said.
A scuffle broke out between Erikson and a male parishioner, before Erikson's female friend said he had gone too far and he walked out.
But Erikson stormed back in and found the male parishioner, filming him while accusing the man of assault. He eventually left and waited outside for police to arrive.
Rev Townsend said Erikson violated a safe space for many LGBTQI Christians and some were so traumatised they could not return to the room.
"We were all very shaken, two members of our church refuse to go into that room after that incident, a number of them had counselling," Rev Townsend said.
"Our church is meant to be a safe space for LGBTI Christians, because at that stage there were so few safe spaces. What Mr Erikson did was take away that aspect so that we no longer had a safe space to worship."
Erikson, who remains on bail and appeared by video link, intends to rely on the constitution as part of his appeal.
He previously tried to access police emails, which the court heard was to show the police response to the incident was politically motivated.
The appeal continues before Chief Justice Peter Kidd.