Government agencies are releasing Christmas and Easter messages from departmental bosses to the bureaucracy for the former public service minister, known for his ardent Christian views and social conservatism.

Senator Abetz has come under fire from the Greens and public policy experts, who said he was wasting the time of agencies that should be allowed to focus on delivering services.

But the Liberal Senate backbencher said people had a right to know the extent of "the infiltration of a political correctness agenda in the public service" that repudiated Australia's long-held traditions.

He has asked more than 80 agencies to release their Christmas, Easter and Ramadan messages.

Department heads in greetings disclosed to the Senate commonly wish their staff a merry Christmas and eschew greetings of "happy holidays" despised by socially conservative critics.

Home Affairs department secretary Michael Pezzullo, writing then as Immigration boss, former Defence secretary Dennis Richardson, and ex-Human Services secretary Kathryn Campbell in 2016 all gave the traditional greeting.

Agency bosses also commonly wished their staff a "happy Easter".

Debate over Christmas messages moved to social media after Tasmanian Greens senator Nick McKim posted on Facebook a tongue-in-cheek photo showing a banner wishing a "merry nondenominational seasonal festivity", in a dig at Senator Abetz.

Senator McKim said the questions from the conservative backbencher showed Christmas messages had become his new obsession after losing the debate over same-sex marriage.

"This is just Eric Abetz fighting imaginary enemies," he said.

"Public servants have better things to do than answer idiotic questions on notice.

"Heads of government agencies are well entitled to send celebratory messages to their staff without having to worry what the right wing culture warriors think about it."

ANU Crawford School of Public Policy director Helen Sullivan said Senator Abetz's questions were a ridiculous waste of time for public servants.

"They've got more important things to worry about than checking on how people are being greeted," she said.

"Of the great range of things Senator Abetz could be dealing with, I don't think this is a particularly important one."

The public service represented all Australians, and this should be reflected in both their holiday messages and their broader work, Professor Sullivan said.

"The APS should not be used as a political football. It's not there for the purposes of people to argue their political differences or to be a new front in the culture war."

Senator Abetz said his questions were very easily answered and included no impost.

"I am pleased to see that, so far, most agencies have no qualms in celebrating Easter and Christmas," he said.

The senator, who presided over the Coalition's hiring freeze and 15,000 job losses, has remained vocal about his views on how the government should manage the public service, calling twice in 2017 for more massive cuts to its headcount.

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