To attend a religious revival event, during which you would be prompted by the preacher to testify.
The act of testifying normally involves babbling incoherently while sharing folksy stories of your nasty life being turned around because the creator of the universe decided to pay you a personal visit and issue a get out of jail free card. He's nice like that, and as a pensioner he has a free bus pass allowing him to travel anywhere in the world.
Peter Popoff: Testify brother!
Hick: Well, I dun gone crashed mah car while drunk, and then I cheated on my sister with mah cousin. I's a sinner, but the baby Jesus came in to mah trailer and fixed me up good. Now I 'aint feelin' no guilt when I'm porking mah cousin.