"Spanish legislation on marriage is gravely unjust — it does not protect the parties' right to be recognized in law as husband and wife, nor the right of children and young people to be brought up as future husbands and wives, and to enjoy a father and mother in a stable family," the bishops' conference said after its Nov. 19-23 plenary in Madrid.
"We call again on politicians to take responsibility. Right reason demands everyone act according to conscience and beyond party discipline in this key area and that no one votes to endorse a law which so badly damages society's basic structures."
The statement follows the Nov. 6 court judgment rejecting legal challenges to the 2005 law.
The bishops said the country was "witnessing the destruction of marriage by legal means," adding that all politicians should uphold the common good by changing the law.