In three months, Dr Williams will leave office after a decade that has seen painful rows over homosexuality and women bishops within the Church, and sizeable shifts in a nation embracing new attitudes and struggling to come out of the worst double-dip recession in 50 years.
In a wideranging interview with The Telegraph, the Archbishop said he feels "massive anxiety" about the Government's austerity programme and notes that it has "not yet delivered what everybody hoped".
In an age of secularism and vocal atheism, it concerns him that two of the three main party leaders are atheists, while David Cameron admits his faith comes and goes.
"It does give me some concern," he said. "That means we have, as people of faith, to encourage our own folk to be a bit more willing to go into politics, and get their hands dirty."
The Church has been at odds with the Government recently over its plans to legalise gay marriage. Dr Williams told The Telegraph that the consultation had been "very inadequate" and overlooked the legal position of the Churches and marriage.
However, he said the Church had been wrong in not doing more to support the civic rights of gay people and its opposition to gay marriage had exposed the Church to accusations of homophobia.
"We've not exactly been on the forefront of pressing for civic equality for homosexual people, and we were wrong about that."
On the question of whether legalising gay marriage would lead to the disestablishment of the Church, the Archbishop said: "We've been assured that there will be no pressure on the Church to perform marriages, but of course as things stand, every citizen has the right to be married in Church.
"That's alright, so long as the State's definition of marriage and the Church's definition are the same. If the State's definition shifts … then we have a tangle."
Reflecting on the future of the office of Archbishop of Canterbury, Dr Williams told The Telegraph the Church was considering a "more presidential figure" to take the helm alongside the Archbishop of Canterbury.
If the Archbishop of Canterbury were no longer the head of the Anglican Communion, he remarks: "It would be a very different communion, because the history is just bound up with that place, that office.
"So there may be more of a sense of a primacy of honour, and less a sense that the Archbishop is expected to sort everything."
The Secretary General of the Anglican Communion issued a clarification saying that The Telegraph's report of a 'presidential' figure had been "inaccurately stated".
Canon Kenneth Kearon said: "There are no such plans. The Archbishop of Canterbury simply said in the interview that he could see that in the future there might be some reflection on how the administrative load associated with the Anglican Communion might be better shared.
"The Anglican Communion has several decision-making bodies, one of which is meeting in a few months' time. Nothing like what this newspaper has suggested is on the agenda."
Following his departure, Dr Williams will take up his new post as Master of Magdalene College, Cambridge.