I'm not familiar with the tune, so I don't know what would fit, but since it was "darkies" to begin with, and "Baptist" now, surely there's a generic, non-offensive substitute word out there....[mission, maybe]

I remember how the song "Methodist Pie" went over like a ton of bricks at a Sunday night/camp meeting-style service at a Methodist Church in my recent past...

And besides, the Baptists could probably use a break.

T: Raised Baptist/In Recovery