The father of Scientology leader David Miscavige appeared on the ABC News show 20/20 Friday night, but the hour-long program added little to the narrative that has been unfolding in the decade since top church insiders began leaving and speaking out.While Ron Miscavige, 80, described his 55-year-old son as hot-tempered and corrupted by power, he gave no firsthand accounts of the violent physical outbursts that others have described, and had no new information about the "Hole," a small building on the church's remote California base where ex-members say Scientology executives were held in degrading conditions behind guarded doors.Still, the interview with ABC anchor Dan Harris represented a compelling moment in the church's recent history.A number of Scientologists who were close to Miscavige have gone public with allegations about him in recent years. They include Marty Rathbun, his former number two man; Mike Rinder, the church's long-time international spokesman; Debbie Cook, who ran the church's spiritual headquarters in Clearwater for 17 years; even the leader's niece, Jenna Miscavige Hill.But Ron Miscavige is both the closest relative to come forward and the one who brought his whole family into Scientology in the late 1960s and early '70s, an act that would end up altering the church's history. INSIDE SCIENTOLOGY: Times coverage of the controversial churchA member of Scientology's uniformed workforce, the Sea Org, since 1985, he told Harris he became fed up with conditions under his son's leadership and escaped the church's remote California compound with his wife in 2012.About three hours before air time Friday, the church issued a short statement, saying in part: "Ronald Miscavige is seeking to make money on the name of his famous son. David Miscavige has taken care of his father throughout his life, both financially and by helping him in even the most dire circumstances. … Any father exploiting his son in this manner is a sad exercise in betrayal."The elder Miscavige's appearance comes as part of the run-up to his new book, Ruthless: Scientology, My Son David Miscavige and Me, scheduled for publication Tuesday. He said he decided to write the book last year after learning from police in the small Milwaukee suburb of West Allis that a father-and-son private investigator team had been following him for 18 months. Officers had discovered the father acting suspiciously in a neighborhood where Ron Miscavige had been shopping for a house to buy.Under questioning, the men said their client was David Miscavige and that they were paid $10,000 a week to watch Ron Miscavige.According to police reports, the men also described a time when they were surveilling the elder Miscavige and he appeared to reach for his chest. Fearing their subject was having a heart attack, the investigators called their contact on the job and said they soon got a return call from David Miscavige, who told them not to intervene.Ron Miscavige told 20/20 that his son's reportedly callous reaction affected him like "a shot to the head. It was like somebody hit me in the chest with a sledgehammer."A church attorney, Monique Yingling, told 20/20 that another attorney had hired the two investigators. She said David Miscavige had nothing to do with it, and never spoke to either of the men.In 1969, after discovering the church by chance during a meeting about a business opportunity, Ron Miscavige began to read books by Scientology founder L. Ron Hubbard and take church counseling known as "auditing." One day, after 9-year-old David was suffering through one his asthma attacks, he took him to a Scientologist and the symptoms abated.The boy was impressed and soon the Miscaviges sold their belongings, left their suburban New Jersey home near Philadelphia and moved to Scientology's advanced organization in England — mom, dad, two sons and two daughters. There, 12-year-old David Miscavige became an ardent follower and later dropped out of high school to join the Sea Org in Clearwater. Thus began a quick rise through the ranks that peaked when he became the church's leader at age 26, not long after Hubbard's death in 1986. It was a journey that many say was powered by David Miscavige's forceful personality.Though the 20/20 interview yielded no startling revelations, it did expose the deep resentments that now divide Scientology's first family. Ron Miscavige admitted he hit his first wife Loretta and expressed regret. But Yingling told the network the domestic abuse was worse than the elder Miscavige admits, and his two daughters released a statement to ABC News saying he struck them with his fists and a belt. "Our father beat our mother senseless in drunken tirades, averaging two violent attacks with his fists per week," their statement said, adding that they have cut off contact with their father.Ron Miscavige said of their allegations: "It's such a lie, it's beyond belief. … I never thought they would resort to this."He said the family now is in the grips of Scientology's disconnection policy, which forbids practicing Scientologists from having any contact with those who criticize the church, even if they are relatives. His eyes filled with tears as he told Harris he had not talked to this grandchildren and has great grandchildren, but no idea how many.Asked by Harris if he would forgive his son after all that has transpired, the father said, "Yeah. It's the only way anybody can move forward. If he were here and if he would do it, I'd shake his hand and give him a hug."Yingling said there was nothing for the father to forgive. David Miscavige, she said, "has done nothing to him but care for him."