Sheldon Troy Graham was on a job site a fortnight ago and said he was talking openly with a co-worker about Jesus while the two worked.

The devout Christian, who admits he wasn't always a religious person, said his decision to introduce God into his life was one of the best decisions he had made and would happily talk to others about his faith.

Mr Graham said he had seen other workers cop abuse for openly discussing their beliefs at work and tried to support them but never felt threatened by anything personally.

He said that all changed after his supervisor told him to ``stop talking about that Jesus Christ s--t'' during a day on the job.

``It hurt me because that is my belief,'' Mr Graham said.

``I have [experienced discrimination], but not to this extent.

``It was expressed in a way that was very unacceptable and if there were children or anyone else around who heard the language that came out of his mouth . ?. ?. I don't think it was very acceptable at all.'' 

Mr Graham said he walked off the job immediately.

He wasn't sacked for leaving, but said he experienced more scrutiny than support when he showed up at the office on Monday morning to tell his side of the story.

``I basically felt the finger was being pointed at me for what I did, and I told them that I did all the right things and they still tried to find some clause in there about why I shouldn't have left the job,'' he said.

``I thought I was within my rights to, and I think I did the right thing.'' 

Mr Graham's employer declined to comment but said it did have procedures in place to deal with his situation.

Mount Isa Catholic priest Father Mick Lowcock said there was a fine line between evangelisation, or trying to convert someone through speaking about your faith, and sharing your views.

He said in a work environment people might be better off practising their faith through their actions instead.

``I think sometimes people get put off because of what people say,'' he said.

``In my mind it's who we are and what we do. Our actions speak louder than what we say.'' 

Father Mick said in a world where work dominated most people's lives we had to be careful about the relationships formed in the workplace.

``The world we live in has changed dramatically and people aren't as careful as they used to be with what they say or the way they go about it,'' he said.

``Most of the time if people don't know another person's situation and start preaching to them they might not realise how it might affect them.

``We have to be careful about moralising what we're about, it's important we're concerned for the person not the principle.'' 

Fair Work Australia classes an incident as workplace discrimination when an employer takes adverse action against an employee or prospective employee because of a protected attribute.

Protected attributes include race, sex, colour, sexual preference, age, religion, physical or mental disability, marital status, pregnancy, political opinion, social origin, national extraction and family or carer's responsibilities.

If you feel you've been discriminated against at work you can contact the Fair Work Commission for advice or visit www.fairwork.gov.au for more information.