David Cameron has ventured into territory avoided even by Tony Blair, the most devout prime minister in living memory, during his time in Downing Street.

As Easter Sunday approaches, Cameron has decided to "do God" in public, as Alastair Campbell might say.

The prime minister, who held an Easter reception in Downing Street, quoted from the Gospel of Luke as he spoke of "we" Christians.

"This is the time when, as Christians, we remember the life, sacrifice and living legacy of Christ. The New Testament tells us so much about the character of Jesus; a man of incomparable compassion, generosity, grace, humility and love. These are the values that Jesus embraced, and I believe these are values people of any faith, or no faith, can also share in, and admire.

"It is values like these that make our country what it is – a place which is tolerant, generous and caring. A nation which has an established faith, that together is most content when we are defined by what we are for, rather than defined by what we are against. In the book of Luke, we are told that Jesus said, 'Do to others as you would have them do to you' – advice that when followed makes for a happier, and better society for everyone."

He told the assembled guests that he welcomed a Christian "fightback". He said: "I think there's something of a fightback going on, and we should welcome that. The values of the Bible, the values of Christianity, are the values that we need."

Cameron's public avowal of his faith contrasts with previous jocular remarks – in a Guardian interview in 2008, the future prime minister said: "I am a sort of typical member of the Church of England.

"As Boris Johnson once said, his religious faith is a bit like the reception for Magic FM in the Chilterns: it sort of comes and goes. That sums up a lot of people in the Church of England. We are racked with doubts, but sort of fundamentally believe, but don't sort of wear it on our sleeves or make too much of it. I think that is sort of where I am."

Blair, a committed Anglican, converted to Roman Catholicism after he left office. Alastair Campbell repeatedly stopped him from talking about his religion, once famously remarking: "We don't do God."