"I have been trying to remind this nation of how all that is of worth in it is based on Christianity," said the Rt Rev Michael Nazir-Ali at CWR's "Jesus in a Plural World" event on Thursday.
"The result of amnesia in this respect would be absolutely disastrous" for Britain, he added.
The Bishop argued that values like tolerance and respect had become what he called "thin values", values that appeal to the lowest common denominator but are not specific enough for people to truly live by.
"In fact, the values we need to live by need to be 'thick' values," he said.
Values such as human dignity, equality and liberty were 'thick', he said, because they are rooted in Christianity and can not be detached from the biblical teaching that all human beings are made in the image of God.
"There is an appeal to a transcendental principle from the Bible that we are made in the image of God. That must be the basis for thinking about human dignity. There can be no other basis upon which we can think about human dignity," said the Bishop.
He added, "It becomes a Christological issue because we cannot know the image of God without looking at Jesus."
Bishop Nazir-Ali urged Christians not to bend to the latest cultural trends.
"Christianity should not be swayed by the Hazel Blears philosophy that all religions are the same," he said, referring to the Communities Secretary, a practising Christian who rejected the Bishop's claim earlier in the year that Islamic extremism is turning parts of Britain into no-go areas.
