VATICAN CITY — Pope Francis accepted the resignation of the archbishop of Washington D.C. over the handling of Catholic Church sex abuse cases, praising the close ally for stepping down in the name of unity rather than fighting accusations of a cover-up.

With his resignation on Friday, Cardinal Donald Wuerl became one of the highest-ranking Catholic leaders to step aside over global accusations that the Church harbored sex abusers.

The cardinal, one of the most prominent Church figures in the United States, has been a strong defender of Francis, who has been criticized by conservatives in the Church, some of whom say the pope himself should resign over the sexual abuse crisis.

In a glowing letter of support, Francis made clear that he accepted Wuerl’s resignation reluctantly, at Wuerl’s insistence, and believed he was not guilty of trying to conceal abuse. “You have sufficient elements to ‘justify’ your actions and distinguish between what it means to cover up crimes or not to deal with problems, and to commit some mistakes. However, your nobility has led you not to choose this way of defense. Of this, I am proud and thank you,” the pope wrote.

Wuerl has come under fire since the release in August of a US Grand Jury report on sexual abuse, which found evidence that at least 1,000 people, mostly children, had been sexually abused by some 300 clergymen over the course of 70 years.

The report covered six diocese in Pennsylvania, including Pittsburgh, where Wuerl served as archbishop from 1998-2006. The report mentioned Wuerl’s name more than 200 times. Wuerl has defended his overall record in Pittsburgh.

In a highly unusual move, Francis asked Wuerl, who keeps the title of cardinal, to stay on as administrator of the Washington diocese until another archbishop could be appointed. Usually a new bishop is announced at the same time as such a resignation.

The Washington position is the most important and visible for the Church in the United States because of its proximity to national political power.

“Francis would want to take his time in finding a successor in sympathy with his vision of where the Church should be going,” said Father Tom Reese, author of several books on the Vatican and the Roman Catholic Church in the United States.

In a statement thanking the Pope, Wuerl said he apologized for “any past errors in judgment”.

“My resignation is one way to express my great and abiding love for you, the people of the Church of Washington,” he said.

The Church has recently been hit by one sexual abuse scandal after another, from Germany, to the United States, to Chile. At the same time, a deepening polarization between conservatives and liberals in the Church has played out on social media.

In his letter to Wuerl, the pope said he recognized that Wuerl wanted to step down for the greater good of the Church. He also thanked Wuerl for “actions that support, stimulate and make the unity and mission of the Church grow above every kind of sterile division sown by the father of lies.”

In Christian parlance, “father of lies” is a synonym for the devil. Francis has said the devil is ultimately behind sex abuse of children by priests and current divisions in the Church.

Wuerl has also been accused of knowing that his predecessor in Washington, ex-cardinal Theodore McCarrick, had forced male adult seminarians to have sex with him years ago. Wuerl denies having been aware.

In July McCarrick became the first cardinal in about 100 years to be stripped of his red hat and title of “eminence”.

Francis ordered McCarrick to retire to a life of prayer and penitence after American Church officials said as part of a separate investigation that allegations that McCarrick had sexually abused a 16-year-old boy almost 50 years ago were credible and substantiated. — Reuters