The former Alliance Party leader was speaking out this week to highlight the fact that the Charity Commission had still not completed an investigation into the denomination after he lodged complaints about it in July 2022.
He resigned as an elder from the church in June 2018, saying he was concerned about a new forthright expression of its stance against same-sex relationships.
He later worked with former Presbyterian minister Roy Simpson to compile a dossier of allegations of bullying and abuse of power against the church, containing interviews with 12 people.