Elton John criticized the Vatican after it declared the Catholic Church cannot bless same-sex unions because God "cannot bless sin".
John, who married his long-term partner David Furnish in 2014, claims the stance is hypocritical as the Vatican invested "millions" in his 2019 biopic Rocketman.
"How can the Vatican refuse to bless gay marriages because they 'are sin', yet happily make a profit from investing millions in Rocketman - a film which celebrates my finding happiness from my marriage to David?? #hypocrisy."
The singer, 73, tagged both the Catholic Church and Pope Francis in his message.
A report that the Vatican invested in Rocketman, as well as Men in Black: International, was published in an Italian newspaper in 2019.
The Vatican said on Monday that priests cannot bless same-sex unions and that such blessings are not valid, in a ruling that greatly disappointed gay Catholics who had hoped their Church was becoming more welcoming under Pope Francis.
A separate explanatory note from the CDF said that while the blessing of same-sex couples was not licit, the decision "in no way detracts from the human and Christian consideration in which the Church holds each person".
It also said that Church could bestow blessings on gay individuals.
"(The ruling) does not preclude the blessings given to individual persons with homosexual inclinations who manifest the will to live in fidelity to the revealed plans of God as proposed by Church teaching," it said.