The full back, capped 73 times by Australia, was found guilty of a code of conduct breach and stripped of his contract for an Instagram post that said “hell awaits” gay people.
Folau’s lawyers, citing section 772 of the Fair Work Act, said it is “unlawful to terminate employment on the basis of religion” and are reportedly seeking AUS$10 million ($7M) in damages.
In a statement from Folau’s legal representatives, the player said: “I will forever be grateful and proud to have played the sport I love for our nation.
“Ours is an amazing country built on important principles, including freedom of religion.
“A nation made up of so many different faiths and cultural backgrounds will never be truly rich unless this freedom applies to all of us.
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“The messages of support we have received over these difficult few weeks have made me realize there are many Australians who feel their fundamental rights are being steadily eroded.
“No Australian of any faith should be fired for practicing their religion.”
In the April post, Folau, a devout Christian, listed “drunks, homosexuals, adulterers, liars, fornicators, thieves, atheists and idolaters,” and wrote underneath, “Hell awaits you.”
The 30-year-old had a contract until 2022 and was expected to represent the Wallabies at this year’s World Cup in Japan.
But on top of his contract being terminated, Folau lost sponsorship deals with companies including car manufacturer Land Rover and sportswear brand Asics.
According to his legal representatives, Folau is seeking “substantial remedies from his former employers should they be found to have breached the Fair Work Act in terminating his employment.”
Folau’s brother quits Waratahs
Folau’s younger brother, John, has been granted an immediate release from his contract by the NSW Waratahs.
Waratah’s coach Daryl Gibson confirmed John’s release at the club’s training base saying: “Obviously we gave John some time off for leave, he’s come back to us recently and asked for a release which we’re happy to grant.
“Obviously John’s been in a difficult position for the last wee while, he’s got really divided loyalties to his family obviously and his brother, but then also to the team.
“He wanted to stress how much he enjoyed being with the team and what a difficult decision that was for him.”
The 24-year-old joined the Waratahs last year but did not make his Super Rugby debut for the New South Wales club.