The Equality and Human Rights Commission's (EHRC) major new report will lambast over-zealous employees who are afraid of references to Christmas or the Lord's Prayer.
Seen by the Mail on Sunday, the report especially criticises a ban an advert featuring the Lord's Prayer.
"I want to put the record straight... you can send Christmas cards and have a Christmas party," he said.
"Freedom of religion is a fundamental human right and it shouldn't be suppressed through fear of offending. Lots of employers have now become really worried about doing anything discriminatory regarding their Muslim or Jewish staff," he added according to the The Sunday Times.
He was particularly critical of the decision by Digital Cinema Media, the advertising arm for Odeon, Cineworld and Vue, to block a Church of England advert for prayer last November.
The report read: "There is no right in Britain not to be offended and, in our view, respect for people's right to express beliefs with which others might disagree, is the mark of a democratic society.
We are concerned that a single supplier is effectively able to control a very large proportion of the market and effectively impose a blanket ban on advertising of a religious nature."
But he stopped short of saying a change in equality laws was needed, something campaigners at The Christian Institute have called for.
"When the EHRC has to remind employers that it's OK to celebrate Christmas, it shows how damaging the influence of the equality industry has been," a spokesman said according to the Mail.
"No one needs to remind employers that it's OK to celebrate gay pride. But celebrating Christmas? Apparently that's dodgy ground. It's crazy."