Christians have been put on notice to be more sensitive in how they share their faith at work, particularly with junior colleagues.

The warning by Christian legal experts follows a case in Britain in which a woman was disciplined for allegedly “harassing and bullying” a Muslim work friend by giving her a Christian book.

Victoria Wasteney, 39, a senior occupational therapist at a London mental health facility, was suspended for nine months and given a written warning after being found guilty of serious misconduct, “namely the blurring of professional boundaries and the subjection of a junior colleague to improper pressure and unwanted conduct.”

Wasteney had claimed she had no idea her approaches were unwelcome when she gave a Pakistani workmate, Enya Nawaz, a book about a Muslim woman’s conversion to Christianity, prayed with her and invited her to church.

Last year, she challenged the decision at an employment tribunal but it ruled her employer, the East London NHS Foundation Trust, had not discriminated against her. She appealed the ruling, saying it had breached her right to freedom of religious expression under the European Convention on Human Rights, but this was dismissed last week by Judge Eady QC in London.

Judge Eady reaffirmed the tribunal’s finding that she had gone beyond voluntary discussion and subjected her subordinate to “unwanted and unwelcome” attention.

The Judge ruled that Wasteney was “not subjected to disciplinary process or sanction because she manifested her religious belief in voluntary and consensual exchanges with a colleague but because she subjected a subordinate to unwanted and unwelcome conduct, going substantially beyond “religious discussion”, without regard to her own influential position.

“The treatment of which the Claimant complained was because of, and related to, those inappropriate actions; not any legitimate manifestation of her belief.”

After the decision Wasteney said: “What the court clearly failed to do was to say how, in today’s politically correct world, any Christian can enter into a conversation with a fellow employee on the subject of religion and not, potentially, later end up in an employment tribunal.

“If someone sends you friendly text messages, how is one to know they are offended? I had no idea that I was upsetting her.”

Neil Foster, Associate Professor of Law at Newcastle Law School, said it was a tricky case because it turned on the facts of what was said in what way and in what context, not on a person’s right to talk about Christianity at work.

“It is a warning for Christians to be sensitive and respectful to others in the way their share their faith in the workplace,” he said.

“In particular, in the modern context where we can no longer accept that Christianity receives general assent, people can be antagonistic to some views, so we need to be careful to speak graciously and respect other people’s ability to say ‘no, thank you I’m not interested in that.’”

He said it was heartening that the court upheld the right to talk to others about religious views in the workplace, including the right to seek to change minds, but it was important to respect other people’s expectations.

“So if you overstep the mark and say things people don’t want to hear and keep pressuring people, your employer may have to take action in the interests of harmony.”

However, he said it could also be a warning to British employers that they can’t shut down all religious discussion in the workplace because the Judge recognised that the right to religious freedom meant it was reasonable for people to be able to talk to others about their faith.

“We don’t have religious freedom protections that are applicable in the UK, so in theory it’s possible in NSW for an employer to discriminate against someone on the basis of their religion without acting unlawfully,” Foster said.

“It illustrates the need for Australian lawmakers to think about appropriate protection for religious freedom to take into account all the interests of people involved.”

Mark Fowler of Brisbane-based NT Lawyers said the fact that the exchanges between Wasteney and Nawaz were ruled not to be consensual meant the claimant’s submission that her rights to religious freedom had been quashed could not be considered.

But he added: “It’s going to be very strange society if we can’t exchange our passionately held views and fundamentally held convictions in a way that is cordial and open and discursive.

“The key thing for Christians is that this should not be seen fearfully as we can no longer share our faith but that consent is a very important part of the process.”