I can understand the need for Christian forgiveness.
However, Greeting him is one thing, but why the need to applaud?
He probably dropped a big fat check in the collection plate. Applause are easy to buy.
You have to understand what's happening here.
The black pastor was not thrilled this guy showed up, so.... he pointed him out. The applause, I'm sure, was very golf-tournament-like, and there was a genuine risk of boos. Also, all the congregation, having been made aware of Sterling's presence, could shoot Sterling death-glares and avoid being near him, so he'd feel even more awkward.