Rugby Australia has described an Israel Folau social media post, in which the full-back says "hell awaits" gay people, as "unacceptable".
Folau, 30, escaped punishment for similar comments last year, with the governing body saying it accepted - but did not support - his "position".
On Wednesday, he posted on Instagram that "drunks, homosexuals, adulterers, liars, fornicators, thieves, atheists and idolaters" should "repent" because "only Jesus saves", and made similar remarks on Twitter.
He sent a tweet criticising the Tasmanian parliament, which has become the first Australian state to make it legally optional to list gender on birth certificates.
In a statement, Rugby Australia said the post "does not represent the values of the sport and is disrespectful to members of the rugby community", adding that its integrity unit had been "engaged on the matter".
Folau's posts were made exactly one year after he met rugby chiefs to limit his use of social media.
Folau signed a four-year deal with Super Rugby side Waratahs in March.