Israel Folau, who's starred for Australia over the past six years, has often spoken about his Christian faith, regularly sharing Bible verses and messages on Twitter and Instagram.
Last year he received much criticism for telling a follower that God's plan for gay people was hell unless they repent of their sins.
His employer, Rugby Australia, had said his comments "did not reflect the views" of the organisation but added: "In his own words, Israel said that he did not intend to upset people intentionally or bring hurt to the game. We accept Israel's position."
His latest post (below) lists a number of different sins (homosexuality) and tells followers that "hell awaits".
Rugby Australia and his club NSW Warratahs have released a statement criticisng his comments.
They say they have failed to get hold of Folau over the past 24 hours but now intend to sack him.
They said: "Whilst Israel is entitled to his religious beliefs, the way in which he has expressed these beliefs is inconsistent with the values of the sport.
"We want to make it clear that he does not speak for the game with his recent social media posts.
"In the absence of compelling mitigating factors, it is our intention to terminate his contract."
Folau has previously defended his comments on the Players Voice website.
In a long article in which he talks about the basics of Christianity, he said: "People's lives are not for me to judge. Only God can do that.
"I have sinned many times in my life. I take responsibility for those sins and ask for forgiveness through repentance daily."
Speaking about his views on homosexuality and sin, he went on to say he was unprepared to "compromise my faith in Jesus Christ, which is the cornerstone of every single thing in my life".
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