The Nobel peace laureate and anti-apartheid hero was lending his support to a UN-backed campaign for gay rights in his native South Africa.
Though same sex marriages are legal in the country, homosexuals still experience brutal violence. Last month a lesbian was found dead, having been sexually assaulted with a toilet brush.
The retired former Archbishop of Cape Town, 81, is a long-standing campaigner for gay rights, and compared the struggle to that for racial equality in South Africa.
He said: "I would refuse to go to a homophobic heaven. No, I would say sorry, I mean I would much rather go to the other place.
"I would not worship a God who is homophobic and that is how deeply I feel about this."