The Archbishop of Canterbury has made a strong call for effective local action to reduce carbon emissions and to maintain pressure on councils and businesses to do the same.
Rowan Williams was speaking at Southwark Cathedral about the looming environmental crisis in advance of the Copenhagen summit in December.
The Archbishop and the Patriarch of Constantinople, head of the Greek Orthodox Church, are planning to be in Copenhagen together to urge government leaders to take bold decisions.
Speaking to over a thousand people in Southwark Cathedral about the Bible's ethical perspective, Archbishop Rowan said: "To act so as to protect the future of the non-human world is both to accept a God-given responsibility and, appropriately, to honour the special dignity given to humanity itself."
Drawing parallels with the financial crisis, Dr Williams warned against looking for a single solution to the complex environmental challenges.
"Many of the things which have moved us towards ecological disaster have been distortions in our sense of who and what we are, and their overall effect has been to isolate us more and more from the reality we are part of.
"The nature of our crisis is such that we can easily fall back on a position that says it isn't worth trying to change our patterns of behaviour, notably our patterns of consumption, because it's already too late to arrest the pace of global warming."
But he later in his address added: "What we do know, or should know, is that we are living inhumanly."
He called for the response to the crisis to be a reality check and a re-acquaintance with the facts of our interdependence within the material world and a rediscovery of our responsibility for it.
"This is why the apparently small-scale action that changes personal habits and local possibilities is so crucial.
"When we believe in transformation at the local and personal level, we are laying the surest foundations for change at the national and international level."
Dr Williams, who was delivering a lecture organised by the Christian environmental group Operation Noah, ended by quoting Moses in the book of Deuteronomy: 'You know it and can quote it, so now obey it. Today I am giving you a choice between good and evil, between life and death. Choose life.'
The evening concluded with the hymn 'Dear Lord and Father of us all/Forgive our foolish ways'.
Other music was provided by the cathedral's Merbecke Choir.
Operation Noah's 25ft ark was displayed in the cathedral's Millennium Courtyard.
For the latest local news and events direct to your inbox every Monday, you need our weekly email newsletter SE1 Direct.
7,000+ locals read it every week. Can you afford to miss out?
Read the latest issue before signing up