Speaking to the gay magazine Attitude, the former Prime Minister, himself now a Roman Catholic, said that he wanted to urge religious figures everywhere to reinterpret their religious texts to see them as metaphorical, not literal, and suggested that in time this would make all religious groups accept gay people as equals.
Asked about the Pope's stance, Mr Blair blamed generational differences and said: "We need an attitude of mind where rethinking and the concept of evolving attitudes becomes part of the discipline with which you approach your religious faith."
In the interview Mr Blair spoke of a "quiet revolution in thinking" and implied that he believed the Pope to be out of step with the public.
He also thought that in Islam there would eventually be a change of heart. "I believe that, ultimately, people will find their way to a sensible reformation of attitudes."
People's thinking had changed fundamentally, he added. He said: "When people quote the passages in Leviticus condemning homosexuality, I say to them - if you read the whole of the Old Testament and took everything that was there in a literal way, as being what God and religion is about, you'd have some pretty tough policies across the whole of the piece."
Referring to his contacts with evangelical groups in the US and elsewhere through the foundation, he said: "I think there is a generational shift that is happening. If you talk to the older generation, yes, you will still get a lot of pushback, and parts of the Bible quoted, and so on. But if you look at the younger generation of evangelicals, this is increasingly for them something that they wish to be out of - at least in terms of having their position confined to being anti-gay."