Pope Benedict XVI has published his first encyclical, or letter to the whole Catholic Church, devoted to the meaning of love and charity.
Pope Benedict says the word love is abused in the modern world
In Deus Caritas Est, or "God is Love", he says physical love must be redefined by Christian faith and attacks modern obsessions with the "commodity" of sex.
Recent associations of God with "hatred and violence" make Christian love "timely and significant", he writes.
The encyclical has been published in seven key languages, including Latin.
In Italy, one million copies will be distributed within the upcoming issue of the country's most popular Catholic magazine.
Written in Pope Benedict's native German, the publication is thought to have been delayed by translation problems.
In the encyclical, the Pope stresses the importance of charity, which he describes as an intrinsic part of Nature: "An indispensable expression of her very being".
He is critical of modern interpretations of Eros, or physical love, while conceding that it has always played a part in human existence.
With Eros reduced to pure "sex", the Pope writes, physical love has become a commodity to be bought and sold. Man himself has become a commodity, he adds.
"This is hardly man's great 'yes' to the body... Here we are actually dealing with a debasement of the human body."
Papal proclamations are often taken as a sign of the possible direction of the Roman Catholic Church.
Theologians are expected to scrutinise Pope Benedict's first encyclical for any hints at how the former head of Catholic doctrine will lead his flock.
Love and charity
Pope Benedict, who succeeded Pope John Paul II last year, has recently been dropping hints about his new teaching document.
Last week he told pilgrims that the "gift" of love between man and woman could develop over time into an unconditional love of Jesus, or "agape". Agape is a Greek word used to describe the unconditional, selfless love taught by Jesus.
The full text of his encyclical elaborates on the distinction between erotic love and God's love for all of mankind.
He also explains how love means Christian charity - giving to those in need, particularly in the developing world, says the BBC's David Willey in Rome.
Parts of the Pope's encyclical were originally written by Pope John Paul II.
This is another example of the debt Pope Benedict feels he owes to the man whose place he has taken at the Vatican, our correspondent adds.