The Chicago-born leader of the Episcopal Church, Presiding Bishop Michael Curry, has accepted an invitiation to preach at the ceremony next Saturday in Windsor, England, officials said. "And so we have fun and pray for them as we speak".
Episcopal Church Presiding Bishop-elect Michael Curry gives waves to the crowd as he arrives at the Washington National Cathedral, Sunday, Nov. 1, 2015, in Washington.
He said: "I'm always nervous at weddings because it is such an important day for the couple - whoever they are".
According to its website, Presiding Bishop Curry has been active in issues of social justice including immigration policy and marriage equality. The historic parish was the first African American Episcopal church built south of the Mason-Dixon line, and welcomed both freed and enslaved people when it was formed in 1824.
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Curry became popular in 2012 after he preached the sermon that came to be known as "We need some insane Christians".
Harry and Markle's selection of an American pastor is a break from royal customized. "Now that Bishop Curry is going to be there, I will be waking up on time to catch his comments", Smith said.
Welby said on Twitter that he was thrilled the couple selected Curry to give the address. He called Curry a "brilliant pastor, stunning preacher and someone with a great gift for sharing the good news of Jesus Christ".
He also hit the headlines in 2012 for a sermon called "We need some insane Christians" in which he discussed the notion that Jesus was "crazy" and that his followers need to be too.
The Dean of Windsor, David Conner, is to conduct next week's service, before Justin Welby officiates as the couple make their marriage vows.