The argument started when a churchgoer told Robert Braxton III, 27, he was sitting in seats reserved for two other church members during Sunday service at the Keystone Fellowship Church, district attorney Kevin Steele said.
He yelled "don't f---ing touch me" after a church member tapped him on the shoulders to let him know he was in someone else's seat,
an affidavit obtained by NBC Philadelphia said.
Witnesses said Braxton started causing a fuss over the seat, but soon calmed down after talking to a church usher and a pastor.
But the situation soon turned violent when Mark Storms, 46, approached Braxton, carrying a gun in his hand and telling the 27-year-old to get out of the sanctuary.
The gun-toting suspect then flashed a Concealed Weapons Permit badge, which the district attorney’s office belives was purchased online.
“When he came over, he had a gun out, escalating the situation,” Steele said at a press conference on Thursday. “Braxton then took a swing at the defendant, punching him in the jaw.”
"F--- you and your fake badge, get the f--- out of here," witnesses recalled Braxton telling Storms. "That's not a real gun," another witness remembered hearing.
Just before punching Storms, Braxton asked, "What are you going to do, shoot me?" according to the court records.
The gunman then opened fire, blasting Braxton once in the chest and again in the right arm.
Braxton was rushed to Abington-Lansdale Hospital, where he died from his multiple gunshot wounds.
