Pope Benedict XVI has confirmed that celibacy “remains obligatory” for Roman Catholic priests.
He also restated the ban on Communion for divorced Catholics who remarry, and on abortion, euthanasia and gay unions which he said were “not negotiable”.
The papal declaration reflects the conclusions of a synod – an assembly of bishops – held at the Vatican in 2005.
Draft legislation is before Italy’s parliament that would give legal status to unmarried couples including gays.
“These values are not negotiable,” the Pope wrote, listing “respect for human life, its defence from conception to natural death [and] the family built upon marriage between a man and a woman”.
“Priestly celibacy lived with maturity, joy and dedication is an immense blessing for the Church and for society itself,” he wrote.
Catholics who divorce and remarry are barred from taking communion, unless they “commit to living their relationship… as friends, as brother and sister”.
Celibacy controversy
Last year, Cardinal Claudio Hummes, head of the Vatican office in charge of priests, said the Church might one day have to review the issue of celibacy.
He said celibacy was not a prescribed doctrine, but self-imposed discipline.
Roughly 150,000 men worldwide have left the priesthood to marry. The Church considers them outcasts.
But in the Middle Ages there was no formal ban on marriage for the clergy.
In fact many Popes had wives, including the 9th-Century Pope Hadrian II.