Dr David Mackereth claimed he has been deemed "unfit" to work as an assessor at the Department for Work and Pensions (DWP) over his view that gender is defined by God.
Concerned other professionals could be dismissed for holding such views, the 55-year-old father-of-four told the Sunday Telegraph: "I'm not attacking the transgender movement.
"But, I'm defending my right to freedom of speech, and freedom of belief."
Dr Mackereth, who had a 26-year career as an NHS doctor, began training in May this year to become a health and disability assessor at the DWP.
The Reformed Baptist from Dudley reported that he was taken aside after questioning his instructor's teaching that said patients should be referred to according to the gender they identified as.
He continued: "I said that I had a problem with this. I believe that gender is defined by biology and genetics. And that as a Christian the Bible teaches us that God made humans male or female.
"I could have kept my mouth shut. But, it was the right time to raise it."
Dr Mackereth subsequently received an email from the agency that employed him and would have contracted his services out to the DWP, saying such an attitude could be considered harassment under the 2010 Equality Act. He was invited to undergo further training.
He responded that he could not bow to the demands being made of him, and the contract was ended as a result.
Premier has contacted the Advanced Personnel Management agency for a comment.
A DWP spokesperson told Premier: "Dr Mackereth made it clear during his training that he would refuse to use pronouns which did not match his own view of a person's biological gender.
"We expect all assessors to handle assessments sensitively and adhere to the Equality Act 2010."
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