A doctor has claimed he was sacked because his Christian beliefs stopped him addressing transgender claimants by pronouns relating to their chosen sex.
Disability assessor Dr David Mackereth said he wanted "the right to practise medicine as a Christian doctor".
He claims the Department for Work and Pensions (DWP) breached the Equality Act and his right to freedom of thought, conscience and religion.
The DWP said it could not comment due to an ongoing employment tribunal.
Speaking outside the tribunal in Birmingham, Dr Mackereth, 56, said: "Last year I was training to do medical assessments for the Department for Work and Pensions and because of my Christian convictions I felt I couldn't use pronouns - the words 'he' and 'she' - in an arbitrary manner.
"I said that in good conscience I couldn't do that. The Department for Work and Pensions took some time to think about it and decided then that I wasn't fit to do the job because of, I would say, my Christian convictions.
"So I am coming to court today because I want the right to practise medicine as a Christian doctor in the way that I always have."
Dr Mackereth, from Dudley, whose case is being supported by the Christian Legal Centre, said he believed "we have to show compassion to all our patients whatever their background".
But he said he hoped the court would see he could not be forced to use language "that I consider to be dishonest and against my Christian faith".
Legal submissions were made in a closed session on Tuesday. Evidence in the case is due to begin on Wednesday.
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