Archbishop Charles J. Chaput of Philadelphia has named Auxiliary Bishop Timothy Senior as rector of Philadelphia's historic St. Charles Borromeo Seminary, saying the bishop will serve in the "demanding but also rewarding" role of priestly formation.

"We need men who are equipped with the maturity, humility, zeal and pastoral skill to bring their people to Jesus Christ in today's challenging new environment," the archbishop said in his June 11 column for the Catholic Standard & Times.

Archbishop Chaput stated that "nothing is more fundamental" to Church renewal than "forming good and holy priests."

Bishop Senior has served as the archdiocese's Moderator of the Curia during what the archbishop called "one of the most painful times" the archdiocese has ever experienced.

Archbishop Chaput's predecessor Cardinal Justin Rigali put a total of 26 priests on leave in response to a March 2011 grand jury report that found credible allegations of sexual abuse or inappropriate behavior against them.

Msgr. William Lynn, the Archdiocese of Philadelphia's former Secretary for the Clergy, is now on trial for child endangerment for allegedly failing to keep suspected child abusers out of  parish positions with regular access to children.

Financial difficulties have also forced the archdiocese to close dozens of Catholic schools.

The archbishop said Bishop Senior has done "an outstanding job under pressure."

"I now need him in other work, equally demanding but also rewarding in a powerful way," he added.

The move is unusual for the Catholic Church in the U.S., since auxiliary bishops rarely head seminaries.

Archbishop Chaput said the present seminary rector, Fr. Shaun Mahoney, told him that he has accomplished all he can in that position. The archbishop said he has been "very pleased" with Fr. Mahoney's service and regrets losing him because of the "vital importance" of his work.

Monsignor Daniel Kutys, the pastor of Sts. Peter and Paul in West Chester, Pa., will replace Bishop Senior as Moderator of the Curia.

The archbishop said that the Catholic Church in Philadelphia is "a river of life" underneath "the hard shell of sins and burdens of the past decade."

"I've seen it in our parishes, our people and our priests," he said. "Well get back to that clean water by the grace of God and our hard work in his service."