Italy's Rocco Buttiglione, who was forced to withdraw as a candidate for EU commissioner, says he plans to push for Christian values in Europe.
Mr Buttiglione, whose controversial remarks about single mothers and gays triggered his rejection by MEPs, said he felt like a "Catholic witch".
He promoted the "theo-con" campaign at a debate in Milan, vowing to "battle for the freedom of Christians".
The Italian foreign minister is to replace him as justice commissioner.
But Mr Buttiglione, a close friend of Pope John Paul II, said the controversy that led to his withdrawal from the proposed new commission was a "gift from God".
He told the audience at the debate in Milan that "if they want a Catholic witch to burn, then here I am".
He again criticised the European Parliament, saying the situation was "very serious, as they have said that for defending my religious beliefs, I cannot be a European commissioner".
"Facing such things, we have to react otherwise they could one day say: as you are Catholic, you cannot be a university professor or teacher," he said.
Italian Foreign Minister Franco Frattini - widely regarded as a team player who shuns the limelight - is due to replace him as justice commissioner.
Cultural war
After Mr Buttiglione withdrew from the commission he said he had been "the innocent victim of an orchestrated campaign".
He said his views about gays had been misquoted, and he criticised the press for superficial coverage.
"I am not an adversary of human rights, I am a champion of them," he said.
"Theocon" - from theological and conservative - is often used to describe a conservative who believes that religion should play a major role in forming and implementing public policy.
The United States' President George W Bush is often referred to as such.
Giuliano Ferrara, a former spokesman for Italian Prime Minister Silvio Berlusconi, also spoke at the debate, saying that "there is a cultural war happening which has to be fought with force and virtue", according to the Spanish news agency Efe.