Six bishops and Lord Carey, the former Archbishop of Canterbury, complained in an open letter the "apparent discrimination" against churchgoers was "unacceptable in a civilised society".
The letter which referred the case of nurse Shirley Chaplin also claimed Christian beliefs on issues such as marriage and homosexuality have been brushed aside by new legislation. In their letter, the bishops said: "We are deeply concerned at the apparent discrimination shown against Christians and we call on the Government to remedy this serious development.
"In a number of cases, Christian beliefs on marriage, conscience and worship are simply not being upheld.
"There have been numerous dismissals of practising Christians from employment for reasons that are unacceptable in a civilised country."
The bishops said Mrs Chaplin's plight was "yet another case in which the religious rights of the Christian community are being treated with disrespect".
They added: "To be asked by an employer to remove or 'hide' the cross is asking the Christian to hide their faith."
In addition to Lord Carey, the letter was signed by Bishop of Winchester Michael Scott-Joynt, former Bishop of Rochester Michael Nazir-Ali, the Bishop of Chester Peter Forster, Bishop of Hereford Anthony Priddis, Bishop of Blackburn Nicholas Reade and Bishop of Lichfield Jonathan Gledhill.
Mrs Chaplin, 54, a Christian nurse re-assigned to an office role after refusing to take off a necklace bearing a cross, will take her case to an employment tribunal in Exeter.
The trust has stated its policy was nothing to do with the crucifix specifically but related to health and safety concerns about patients grabbing necklaces. But Mrs Chaplin claims the Royal Devon and Exeter NHS Trust Hospital was trying to prevent her from expressing religious beliefs, and argues she has worked for the NHS for 30 years without her cross causing anyone an injury.
Trust human resources director Lynn Lane said: "The trust has fully acknowledged that this has become an important issue for Mrs Chaplin, which is why we offered her a number of different options in the hope that a mutually acceptable solution could be agreed. We are very disappointed that this matter could not have been resolved before now.
"For the trust, this has always been about compliance with our agreed uniform policy and the safety of staff and patients. Our policy on necklaces accords with most other trusts' dress codes and Department of Health guidelines.
"Sadly, it appears that Mrs Chaplin may have been deflected from agreeing a sensible and pragmatic resolution of this dispute by the involvement of other parties outside the trust." The case follows that of Nadia Eweida, 58, who in February lost an appeal against a ruling which cleared British Airways of discrimination by stopping her wearing a cross visibly at work at Heathrow.
She had been backed by Archbishop of York Dr John Sentamu who argued against the "flawed reasoning" which allowed male Sikh staff to wear turbans and female Muslim staff to wear hijabs.
The Archbishop also suggested as Britain's national airline, the company ought to consider the place of the Christian values represented by the Cross.
He refused to comment on the bishops' letter yesterday. A spokesman said his views on people being able to wear crosses at work were already on record.