When the Spitzer governorship fell under the weight of the recent sensational sex scandal, Mr. O’Byrne became the gatekeeper of the new regime in Albany. In a city of colorful resumes, Mr. O’Byrne’s stands out. He abandoned a promising career in law to seek formation as a diocesan Catholic priest and, later, a Jesuit. At times, his chief parishioners seemed to be the Kennedy family, to whom he became a confidant after befriending Stephen Smith Jr., the nephew of President John F. Kennedy, in law school. But within Jesuit circles, Mr. O’Byrne is the consummate “ambitioning prelate,” who left the Order and the church and published a 4,000-word piece in a 2002 issue of Playboy in which he wrote about “the fundamental dishonesty of the church’s leadership.” Born in what is today St. Luke’s Hospital in New York, to a father who taught in New York public schools and a mother who worked as a psychologist, Mr. O’Byrne, 48, spent his first years in Manhattan and Staten Island before moving to Oceanport in New Jersey at the age of five. He attended Red Bank high School, off the Navesink River on the Jersey Shore, and after graduating in 1977, he attended Columbia University, earning his degree in 1981. In 1984 he earned his law degree, also from Columbia, where he and Mr. Smith Jr. became good friends. His first job out of law school was a corporate litigator for the white-shoe firm Rosenman & Colin, but after four years there, O’Byrne found a different vocation. In 1989, he attended Saint Andrew Hall, the Jesuit Novitiate in Syracuse, for his primary formation as a Jesuit. Mr. O’Byrne accepted the invitation of the president of St. Peter’s College to work as an assistant. On the day a jury acquitted Stephen Smith’s brother, William Kennedy Smith, of rape in 1991, Mr. O’Byrne, then a seminarian, attended mass with the family and spent the day in the courtroom. Mr. O’Byrne went on to seminary at the Weston Jesuit School of Theology in Cambridge in 1994, He double-majored in two theological disciplines at Weston, he worked as a popular teaching fellow at Harvard University with Robert Coles, the Pulitzer-prize winning author and child psychiatrist. In 1996 he was ordained a priest and he married JFK Jr. to Carolyn Bessette in South Carolina. After a long hiatus, he returned to politics in 2002, joining the Howard Dean campaign in the summer of 2003 as a researcher, policy director and speechwriter. Eventually, he caught wind that David Paterson, then in his second year as Senate minority leader, was looking for hires. He joined as a speech writer, and climbed the ranks to become communications director and then deputy chief of staff. On November 14, 2006, Paterson appointed Mr. O’Byrne his chief of staff in the Lieutenant Governor’s office. And on Monday March 17 2008, when Paterson is sworn in, the new chief of staff to the governor of New York was close at hand.