The host of the television program, Gianluigi Nuzzi, said in an interview: “I’ve never heard of a top cleric who reveals episodes of corruption directly to the pope; it’s a first. And what happens? He is stopped from pursuing his objectives and gets sent away from the Holy See.”

But the Vatican dismissed the program as “superficial and biased,” and the Rev. Federico Lombardi, a Vatican spokesman, said that the choice of Archbishop Viganò for the post in Washington, “one of the most important roles in Vatican diplomacy, given the importance of the country and of the Catholic Church there, is proof of unquestionable respect and trust.”

Beyond the content of Archbishop Viganò’s letters, in which he said he was working to correct “corruption, private interests and dysfunction that are widespread in various departments,” experts on the Vatican were intrigued that the letters had become public at all. (In his statement about the program, Father Lombardi expressed “disappointment at the revelation of reserved documents,” signaling that the letters were authentic.)

Marco Politi, a Vatican correspondent for the newspaper Il Fatto Quotidiano and the author of a book about the pope, said in an interview that there were signs that “discontent is growing” with Cardinal Bertone’s administration.

“This shows once again that Bertone does not know how to manage the Vatican machine,” Mr. Politi said. “It also shows that there is tension within the Curia, because that’s how the letters got out.”