Kagame became president of Rwanda in 2000, six after the genocide that left around one million people dead within about 100 days.
After he successfully stopped the genocide, Kagame brought back the vice president and reinstalled him. Under his leadership, Rwanda has been lauded as Africa's "biggest success story" and a model example of reconciliation.
The much-praised African leader said the role of the church in Rwanda's reconciliation process was to be a voice to point out when the government was wrong. But during the genocide, the church and government "were almost one and the same" so the church could not distance itself from the action of the government, he explained.
"Today the role is significant and the church has grown back to play its role," Kagame said.
The role of the government, meanwhile, was to embrace everyone and "bring them together".
During the civil forum, Kagame was joined by prominent Yale theologian Milaslov Volf from Croatia.
Volf, who lived through the Bosnian conflict, said there was "always a deep rage" down in his soul during the conflict because of the injustice being done. But he said loving one's enemies is the truly Christian response in such a situation.
"To forgive is an act of power. When I forgive, I'm in charge," Volf said. "I'm releasing you from the wrong."
Both Kagame and Volf have seen their "nearly destroyed" countries get back on the path of reconciliation and were at Saddleback Church in southern California to share their wisdom.
Pastor Warren said though the United States has not experienced a genocide, the stories of reconciliation are relevant because the country is also hurting from many divisions.
Friday's event was the fourth Saddleback Civil Forum, which involves high-profile figures speaking on sensitive issues. Last year, the megachurch hosted then presidential hopefuls Barack Obama and John McCain who spoke about such issues as religious persecution, Aids, abortion, marriage and stem cells.