Former Archbishop of Canterbury Lord Carey claimed Christians of “deep faith” were being penalised as he launched a campaign aimed at speaking up for Christian values in public life.

Lord Carey gave his backing to the Christian Concern “Not Ashamed Day”, urging Christians to “wear their faith with pride” in the face of alleged attempts to “airbrush” them from public life.

He said Christians in recent years had been penalised for activities such as wearing crosses and offering to pray for other people.

“Christianity is a public religion, always has been and always will be,” he said.

“What we believe in is of paramount importance to our nation and were we to lose it, then I have no idea what will happen to the Christian faith in this country.”

The former archbishop warned that Britain’s Christian culture is “under attack”.

The campaign aims to highlight a series of cases involving Christians who have lost claims for discrimin-ation.

These include Nadia Eweida, the British Airways worker from London, and Shirley Chaplin, the NHS nurse from Kenn, Exeter, who both lost high-profile discrimination claims over wearing crosses at work.

Lord Carey was joined in Westminster, central London, by Gary McFarlane, 49, a Christian marriage guidance counsellor from Bristol who lost a court bid earlier this year to challenge his sacking for refusing to give sex therapy to homosexuals.

His application to appeal was dismissed in spite of a call from Lord Carey for a specially-constituted panel of judges with a “proven sensitivity and understanding of religious issues” to hear the case.

In the leaflet, Lord Carey said the attempt to “airbrush” the Christian faith “out of the picture” was especially obvious as Christmas approaches.