The Westboro religious clan, best known for picketing military funerals and gay weddings, also has a problem with the 56-year-old country singer.
"What are you doing with another man's wife?" a protestor asked. "Don't you know that divorce plus remarriage equals adultery? Jesus said that."
Gill divorced Janis Oliver in 1998 and remarried Christian pop singer Amy Grant in 2000.
"[Jesus] also said a lot of stuff about forgiveness, about grace. You guys don't have any of that," Gill hit back.
"Don't you know that you [expletive] are lucky that you don't have a sign that says something about my wife?" he added.
Gill then turned toward another protestor and said, "I’ve seen you on TV, man. You’re a big dipsh**.”
Watch their conversation in the video below: