A rally was held in the Waterfront Hall in Belfast on Tuesday night in support of the Ashers Baking Company ahead of a legal case on Thursday that is being taken against the Christian bakery by the North's Equality Commission.
Ashers, which has six shops employing 62 people, is being prosecuted for refusing to bake a cake with a slogan stating "Support Gay Marriage". It was also to feature the Sesame Street puppets, Bert and Ernie, with their arms around one another.
The civil court case opens on Thursday morning in Belfast and is expected to conclude on Friday.
Members of the McArthur family which owns the bakery and representatives of the British Christian Institute, which is supporting the company in the legal case, joined supporters in the Waterfront Hall last night for a pre court case rally.
The 2,500-seater Waterfront Hall was full to capacity with hundreds more who turned up unable to get inside.
Colin Hart, director of the institute, said "that the overwhelming majority of people in Northern Ireland think that the McArthur family should not be forced to endorse a cause with which they profoundly disagree".
First Minister Peter Robinson also entered the argument this week by accusing the commission of spending up to £33,000 to seek court damages of £500 from Ashers.
“The issue here is, where there are competing rights, ensuring that there is reasonable accommodation. That is what the Equality Commission have missed in all of this,” he said.
“When you consider that they have set aside the potential of spending £33,000 on this court case where they are seeking damages of £500 against Ashers, there is a better use that could be put to that money, particularly in the tight fiscal situation the Executive faces,” added Mr Robinson.
The Equality Commission said it has spent £8,586 so far on the case with the maximum spend to be no more than £33,000.
“The Equality Commission has an important role in ensuring effective application of Northern Ireland’s equality laws and supports cases so that people are aware of, and can avail of, the protection these laws afford against all forms of unlawful discrimination,” it said.
“This case raises issues of public importance regarding the extent to which suppliers of goods and services can refuse service on grounds of sexual orientation, religious belief and political opinion,” added the commission.
Arising from the case DUP Assembly member Paul Givan has published a private member's bill seeking to enact a conscience clause that would allow for a "reasonable accommodation" between the rights of people not to be discriminated against and the right to freedom of conscience of religious believers.
Sinn Fein said with support from other Assembly members it will use a petition of concern – an effective vetoing measure – to block the bill.