"I've received nothing but support from my colleagues and students," he said in an interview.
The school's administration said it fired Griffin because his teaching contract requires him to follow the teachings of the church as a condition of his employment, and he has not done so.
Federal laws offer no protection against discrimination because of sexual orientation in private workplaces, but almost half of the states, including New Jersey, have laws that prohibit sexual orientation discrimination in public and private jobs.
Which is why Griffin said his next job will probably be in the Garden State, where he lives with his partner.
"I know there are protections for me there," he said. "After what I've been through, I think I would like to work in a place where I know my job is secure."
On Friday afternoon, Griffin was told by the Rev. James McCloskey, president of the school, that he was being let go because he mentioned in an e-mail to principal Jeff Danilak that he was applying for a marriage license n New Jersey.
Though Griffin said administrators knew he was gay, McCloskey told him the e-mail to Danilak made his relationship public, which was why he was being fired.
Richard Shaginaw, a 1970 alumnus of Holy Ghost, said he and other classmates were considering writing to the president, who was also in their class, and asking for more information.
Shaginaw called the firing an injustice.
"My biggest concern is what this says to young gay men," said Shaginaw, who works in Princeton at Bristol-Myers Squibb.
He said the decision to fire Griffin was probably very painful for McCloskey, who was required to uphold church teachings that gay marriage is morally wrong.
"The administration is clearly between a rock and a hard place," Shaginaw said.
According to a statement released by McCloskey on Sunday, he had "no choice" but to fire the teacher after learning about his impending marriage. "Unfortunately, this decision contradicts the terms of his teaching contract at our school, which requires all faculty and staff to follow the teachings of the church as a condition of their employment," it said.
Rita C. Schwartz, president of the National Association of Catholic School Teachers as well as its Philadelphia chapter, said that if a gay teacher asked her about going public with marriage, she would tell him or her not to because it violates his or her contract.
"Most times the church is, 'Don't ask, don't tell,' " Schwartz said. "But if they're going to flaunt it, it's going to kind of smack them in the face. I don't think there's much that [Griffin] can do."
It's the same as heterosexual teachers who are divorced and remarry, she said. If the school finds out the first marriage was not annulled, they can be fired.
"We know going in what we're about," Schwartz said. "You're supposed to give witness to the faith as a teacher. You can do it quietly . . . but don't stick a fork in their eye."
Griffin, 35, of Mount Laurel, said his relationship with his partner, Vincent Giannetto, was well known. They had attended parties together with priests, sat with the principal at an April fund-raiser, and invited a school administrator to the reception for their civil union in 2008.
Griffin said he did not know if he had any legal recourse but planned to talk to a lawyer. His priority - besides his wedding, which he wants to keep private so "it's not a circus" - is finding a new job at a public school or a non-Catholic private school, he said.
Though he is not a practicing Catholic anymore, Griffin said, he likes being in a place where he can discuss issues of faith. He said he stopped going to Mass a few years ago because he "felt attacked."
Bensalem school board member Kevin McKay, a classmate from Holy Ghost, offered to pass his resumé along to that district's human resources office.
"We're always looking for good teachers, and I don't know of anything that was adverse in his performance," said McKay, an engineer. "Our policy is not to discriminate on the basis of sexual orientation."