The pastor of Saddleback Church in California addressed senior African church and political leaders at the African Biblical Leadership Initiative (ABLI) conference in Kigali, Rwanda on Wednesday.
He said 17 years ago he and his wife Kay visited a village church in Africa where the congregations was caring for orphans with AIDS.
"I looked at them and I said 'this poor, rural African village church is doing more to help the poor than my rich mega-church in America.'
"It was like a knife in my heart and I said, 'I have to repent'."
Warren told the audience, which included Rwanda's Prime Minister Édouard Ngirente that he had heard God saying to him, "you just don't care about the people I care about most - the poor".
He continued: "Does God have favourites? Yes, he does. He loves the poor."
Warren also spoke of the involvement of Saddleback Church in Africa, and in Rwanda in particular.
Rwandan President Paul Kagame has spoken at the church, and Warren became a dual-nationality Rwandan citizen 15 years ago.
He encouraged his audience to "celebrate Africa", highlighting the progress Rwanda has made since the 1994 genocide in which an estimated 1 million people died.
'The future of the Church is the global south, particularly Africa and Asia,' Warren said.
ABLI, now in its ninth year, is sponsored by Bible Society and this year is hosted by the Bible Society of Rwanda.
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