The Vatican's orthodoxy office specifically focused on issues such as masturbation, homosexuality and marriage which Sister Margaret Farley wrote about in "Just Love: A Framework for Christian Sexual Ethics," saying they posed "grave harm" to the faithful.
In a statement, the Vatican said the book, which justifies masturbation, homosexuality and divorce, "affirms positions that are in direct contradiction with Catholic teaching in the field of sexual morality," according to Agence France Presse.
Farley, a member of the Sisters of Mercy religious order and emeritus professor of Christian ethics at Yale Divinity School, said on Monday that she did not intend for the book, published in 2006, to reflect current official Catholic teaching, according to the AP.
In the book, Farley wrote, "Masturbation usually does not raise any moral questions at all. It is surely the case that many women have found great good in self-pleasuring... (which) actually serves relationships rather than hindering them," according to AFP.
On homosexuality, she said, "same-sex relationships and activities can be justified according to the same sexual ethic as heterosexual relationships and activities."
The Congregation for the Doctrine of the Faith, which examined the book, said, "masturbation is an intrinsically and gravely disordered action" and called homosexual relations "acts of grave depravity," AFP reported.
The criticism comes two months after the Vatican rebuked the umbrella body that represents American Catholic nuns, saying it promoted radical feminist ideas and challenged the church's teaching, according to Reuters.
The Vatican said Farley's writings are "not in conformity with the teaching of the Church" and banned use of the book among Catholic educators. The statement was signed by department head Cardinal William Levada, an American, and approved by Pope Benedict.