The Archbishop began his final Easter sermon arguing that young people's hostility towards faith is not as extreme as society perceives it to be.
He said that many young people take the issue of religion seriously, despite not attending Church.
He warned that now was the "worst possible moment" to downgrade the importance of teaching religion in secondary schools.
There is plenty to suggest that younger people, while still statistically deeply unlikely to be churchgoers, don't have the hostility to faith that one might expect. They at least share some sense that there is something here to take seriously when they have a chance to learn about it. It is about the worst possible moment to downgrade the status and professional excellence of religious education in secondary schools.
Dr Williams, who will take up a post at Cambridge University in January, also told followers that the ultimate test of the Christian religion is not whether it is useful or helpful to society but whether or not its central claim - the resurrection of Jesus Christ - actually happened.
We are not told that Jesus 'survived death'; we are not told that the story of the empty tomb is a beautiful imaginative creation that offers inspiration to all sorts of people; we are not told that the message of Jesus lives on. We are told that God did something
Dr Williams' ministry has been challenging at times. Under his leadership, the Church of England nearly split over the ordination of gay clergy and women bishops.
Dr Williams has shown no resistance to the appointment of openly gay bishops, as well as showing continued support for the ordination of women.
He will continue to carry out all the duties and responsibilities of the Archbishop of Canterbury, both for the Church of England and the Anglican Communion, until the end of the year, Lambeth Palace said.