The Canadian Conference of Catholic Bishops (CCCB) is calling upon Canadians to undergo "a personal and collective conversion" for the sake of the planet.

"Many of us could probably decrease by a ton the greenhouse gases we produce annually," note the bishops in their new pastoral letter, entitled "Our Relationship with the Environment: The Need for Conversion". They also take the Canadian Government to task for allowing carbon emissions to increase by a quarter since 1990 and for giving too little foreign aid to developing countries.

In today's context, declare the bishops, "Selfishness is no longer merely immoral, it is becoming suicidal. We no longer have a choice about new solidarity and new forms of sharing." Produced by the CCCB's Episcopal Commission on Social Affairs, the letter is the bishops' first in a year and a half and a self-described follow-up to their 2003 pastoral letter on the Christian "ecological imperative". However, one prominent Canadian theologian who specialises in ecological issues told The Tablet that this latest document was "less theologically rich" and considerably more problematic than its predecessor.

"It talks about God creating out of chaos and bringing order to the universe," said Stephen Scharper, co-author of The Green Bible and columnist for The Toronto Star. "Theologically, that's very controversial, because traditionally, Christianity saw the Divine creating ex nihilo - out of nothing - and creating not to bring order but to be in loving relationship with Creation ... That is missing in this document and it's fundamental for any ecological theology."

From a different perspective, Paul Tuns, a conservative Catholic blogger and editor-in-chief of Canada's pro-life, pro-family newspaper The Interim, was also critical of the document. "A lot of the letter sounds like warmed-over socialism, such as the need to share resources and for people to turn their back on consumption," he said. "The letter is mostly silent on the difference between the Catholic understanding of good stewardship and current popular environmentalism. It seems to place the good of the Earth and the good for people on an equal plane." The letter won praise from activists outside the Church. Nathan Cullen, the environment critic for the opposition New Democratic Party, told the Toronto-based Catholic Register: "I see [the bishops'] criticisms as accurate and imperative to make."