ROME — Pope Francis demanded absolute loyalty from his ambassadors Thursday, following months of pressure after a former nuncio accused the pontiff of covering up for serial sex abuser Theodore McCarrick.

In his written address to papal envoys gathered in the Vatican, the pope said that in all circumstances a nuncio must be unconditionally “the pope’s man.”

“Being the pope’s representative is therefore irreconcilable with criticizing the pope behind his back, writing blogs, or joining groups hostile to him, the Curia and the Church of Rome,” Francis said.

Last August, the former papal nuncio to the United States, Archbishop Carlo Maria Viganò, released a bombshell 11-page report in which he made a series of allegations regarding high-ranking Church officials, including the pope himself.

Former cardinal McCarrick enjoyed a “long friendship with Cardinal Bergoglio,” now Pope Francis, and played an “important part” in his recent election to the papacy, the archbishop claimed, which led the pope to continue using McCarrick as a trusted aide in the appointment of bishops even after learning of his crimes.

Viganò declared that he had personally informed the pope of McCarrick’s abuse on June 23, 2013 and yet Francis “continued to cover for him.”

“Holy Father, I don’t know if you know Cardinal McCarrick, but if you ask the Congregation for Bishops there is a dossier this thick about him,” Viganò claims to have told the pope. “He corrupted generations of seminarians and priests and Pope Benedict ordered him to withdraw to a life of prayer and penance.”

Nonetheless, Pope Francis “did not take into account the sanctions that Pope Benedict had imposed on him and made him his trusted counselor,” Viganò said.

Pope Francis “knew from at least June 23, 2013 that McCarrick was a serial predator,” Viganò stated, and yet, “although he knew that he was a corrupt man, he covered for him to the bitter end; indeed, he made McCarrick’s advice his own.”

For months following these revelations, the pope refused to confirm or deny them, adopting a policy of strict silence.

Finally, in a lengthy Spanish-language interview last month Francis broke his 9-month silence regarding what he knew of ex-Cardinal Theodore McCarrick’s behavior.

“About McCarrick I knew nothing — obviously — nothing, nothing,” the pope told Mexican reporter Valentina Alazraki.

“But you know that I knew nothing about McCarrick, or I wouldn’t have kept silent, would I?” he asked. At the same time, the pope said he was not sure whether his former nuncio had told him about McCarrick.

Regarding the alleged 2013 meeting with Viganò, the pope said, “I don’t remember whether he talked about this with me, whether it’s true or not. No idea!”

In his address Thursday, however, the pope did not attempt to conceal his bitterness.

A nuncio must be a “man of God,” the pope said, and a “man of God does not deceive or defraud his neighbor; he does not let himself fall into gossip and rumors; he preserve a pure mind and heart, keeping his eyes and ears from the filth of the world.”

“The nuncio who forgets he is a man of God ruins himself and others; he goes off the rails and also damages the church, to which he has dedicated his life,” he said.

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