Gary McFarlane claimed he was discriminated against as a Christian
Judges risk "civil unrest" by ignoring religious beliefs in their rulings, a barrister acting for a sacked relationship counsellor warned a court.
Devout Christian Gary McFarlane, 48, wants to challenge an employment tribunal ruling which supported his sacking by Relate Avon in 2008.
Mr McFarlane, from Bristol, refused to give sex therapy to homosexual couples.
His barrister, Paul Diamond, told the Court of Appeal religious freedoms in the UK now "counted for nothing".
He added: "There will be a collision between the established faith of this land and judicial decisions and that will lead to civil unrest."
Lord Justice Laws also received a message from the former Archbishop of Canterbury Lord Carey.
He said Mr McFarlane's appeal should be heard by a specially-constituted panel of judges with a "proven sensitivity and understanding of religious issues".
Lord Carey said it was "but a short step from the dismissal of a sincere Christian from employment to a religious bar to any employment by Christians".
"The fact that senior clerics of the Church of England and other faiths feel compelled to intervene directly in judicial decisions and cases is illuminative of a future civil unrest," Lord Carey said.
Mr McFarlane had worked for the national counselling service since 2003 and alleged unfair dismissal on the grounds of religious discrimination.
The judge has reserved his ruling on whether permission could be granted for an appeal.