More than 8,000 people have signed a petition backing Ashers bakery in the same-sex marriage cake row, as the case returns to court today.
The McArthur family, which runs Ashers Baking Company, will be at the Court of Appeal in Belfast today in a bid to overturn a judge's ruling that they had broken discrimination laws.
A judge at Belfast County Court ruled Ashers had acted unlawfully by declining an order from gay rights activist Gareth Lee last year.
Mr Lee, a member of the LGBT advocacy group Queer Space, wanted a cake featuring Sesame Street puppets Bert and Ernie with the slogan 'Support Gay Marriage'.
Supporters of Ashers, which refused to make the cake on the grounds it conflicted with their religious beliefs, have also welcomed leading gay campaigner Peter Tatchell's change of heart on the controversy.
The veteran activist this week stepped away from his former criticism of the bakers' stance to one of support for their freedom of speech and conscience.
Members of the Christian Institute, who have held four public meetings in support of Ashers owners, Colin and Karen McArthur, said their petition has topped 8,000 since it was set up on January 23.
The petition, which states, "I support Ashers Baking Co and the McArthur family in their stand for freedom of speech and freedom of conscience" is part of a campaign that has included support rallies in Craigavon, Ballymena, Belfast and Clogher Valley.
At the final meeting in Co Armagh this week, Simon Calvert, deputy director of The Christian Institute, said: "Something has gone wrong when good people like the McArthurs are being hauled before the courts just for holding to that simple view.
"People must be free to manifest genuine, reasonable moral and religious convictions without fear of unfair discrimination and mistreatment."
He said a small number of gay activists with placards and rainbow flags protested outside the meeting.
Mr Tatchell wrote in a national paper this week that he now believes the original court decision, which he had previously supported, was wrong and set a "worrying precedent".
"Much as I wish to defend the gay community, I also want to defend freedom of conscience, expression and religion," he wrote in the Guardian. "In my view, it is an infringement of freedom to require businesses to aid the promotion of ideas to which they conscientiously object. Discrimination against people should be unlawful, but not against ideas."
Welcoming Mr Tatchell's public rethink, Mr Calvert said: "His comments get right to the heart of the problem with the original ruling - that it confused disagreement over a campaign slogan with discrimination against an individual."
He stated that Mr Tatchell had "stood up in the past for the free speech rights of Christian street preachers. Now he is standing up for the rights of the McArthurs and we are grateful to him."
The two-day hearing that starts today will seek to overturn the County Court ruling that Ashers had illegally discriminated against Mr Lee on the grounds of political and sexual orientation.
The McArthur family were ordered to pay Mr Lee £500 in compensation.
The petition is available at christian.org.uk/supportashers