The Vatican criticized a popular American nun on Monday, saying her book on sexual ethics, including topics such as masturbation and homosexuality, contradicts Catholic teaching and must not be used by Catholic educators.

The Vatican’s Congregation for the Doctrine of the Faith issued a stern “notification” about Sister Margaret A. Farley, a member of the Sisters of Mercy and a professor emeritus of Christian ethics at Yale University.

The church body said her writings manifest a “defective understanding of the objective nature of natural moral law” and pose “grave harm to the faithful.”

Two months ago, the Vatican issued a stinging report saying that the umbrella body representing most American Catholic nuns promoted radical feminist ideas and challenged bishops.

Monday’s notification, signed by department head Cardinal William Levada, an American, and approved by Pope Benedict XVI, attacked Farley’s award-winning 2006 book, “Just Love: a Framework for Christian Sexual Ethics.”

The review of the book took years, as the Vatican repeatedly urged Farley to change her text. She refused, explaining in letters to Rome that the book was intended not to represent church teachings but rather to help readers move beyond a reflexive “taboo morality” and think through sexual ethics in the context of justice, wisdom and love.

“I do not dispute the judgment that some of the positions contained within it are not in accord with current official Catholic teaching,” Farley said in a statement issued Monday. “The book was not intended to be an expression of current official Catholic teaching, nor was it aimed specifically against this teaching. It is of a different genre altogether.”

Several Roman Catholic theologians issued statements Monday describing Farley as a serious scholar and insightful theologian. Sister Patricia McDermott, president of the Sisters of Mercy of the Americas, expressed “profound regret” at the Vatican’s action.

The Vatican rejected Farley’s views on masturbation, homosexual acts, homosexual unions and remarriage after divorce.

Farley writes that masturbation, particularly by women, “usually does not raise any moral questions at all” and that it “actually serves relationships rather than hindering them.”

The Vatican said the church teaches that masturbation is “an intrinsically and gravely disordered action.”

Farley writes that “same-sex oriented persons as well as their activities can and should be respected.” The Vatican said that while homosexual tendencies are not considered sinful, homosexual acts are “intrinsically disordered” and “contrary to the natural law.”

— Reuters