Known to member Anna Barry as simply "Brother Nelson," Prince (whose real name was Prince Rogers Nelson) was "in good standing," and would go door-to-door with the ministry, she tells PEOPLE.
"He [witnessed] in the beginning," Barry explains. "He had a very special territory. He was able to talk to those who the rest of us would never be able to talk to – celebrities, for example."
Prince, who died on Thursday at age 57, regarded the Kingdom Hall as a "safe place" and a "haven," Barry says, and toned down his famously colorful style around the congregation.
"He would just have a suit and tie. You wouldn't have picked him out," Barry says, adding, "You wouldn't have picked him out [from the rest of the congregation]."
Prince converted to the Jehovah's Witness religion in 2003, and, with it, "found fulfillment," a church spokesperson said in a statement to PEOPLE.
Barry says that she last saw Prince at a service on March 23 (looking "absolutely normal") for the Jehovah's Witnesses' Memorial of Christ's death – a sacred day in the church.
"I was standing in the back and facing the door and waiting for someone I'd invited, and I was standing there talking to a Brother, and Prince had been at meetings at a couple different locations," she shares. "I was just standing there and all of a sudden, in he walks. I thought, 'He just wants to be treated like an average person,' so I just kind of acknowledged him, and he came in and sat down."
David Brewster / Minneapolis Star Tribune / Zuma
Devoted Jehovah's Witness Prince Kept a Swear Jar at Paisley Park: 'He Wasn't Joking,' Says Congregation Member
Prince passed away at his Paisley Park estate in Chanhassen, Minnesota, on Thursday. He was found alone and unresponsive, and declared dead by the authorities under 25 minutes later. A cause of death has yet to be revealed, but Prince's autopsy was completed on Friday.
Authorities said that Prince's body showed no obvious signs of trauma, and that they had "no reason to believe that this was a suicide."
"When the news comes out about how he died, if indeed it was an overdose, I would feel like he was a victim of a plague that's affecting many levels of our society," Barry says of rumors that Prince overdosed just under a week before his death. "If that was indeed it. I hope it isn't. But I would see him as a victim as opposed to someone who made that choice."