Pope Benedict yesterday concluded his visit to Croatia by denouncing the "disintegration" of family life in Europe.
He made an impassioned appeal for couples to make a commitment to marry and have children, and not just live together.
The Pontiff also revisited his approach to traditional Catholic family values, including opposition to abortion, during an open-air Mass attended by about 400,000 people at Zagreb's hippodrome, the highlight of his trip to mark the local church's national day of families.
The faithful, who came in droves from across Croatia and surrounding countries, arrived before dawn.
The sun shone through the clouds as Pope Benedict celebrated Mass before a crowd of flag-waving faithful, whose numbers exceeded 300,000.
It was his first official visit to Croatia, an overwhelmingly Catholic Balkan nation that is poised to soon join the EU.
The Vatican has strongly supported its bid, eager to see another country with shared values join the 27-member bloc.
Yet, while Croatia is nearly 90pc Catholic, it allows some legal rights for same-sex couples and permits abortion up to 10 weeks after conception.
Pope Benedict lamented the "increasing disintegration of the family, especially in Europe" and urged young couples to resist "that secularised mentality, which proposes living together as a preparation, or even a substitute, for marriage".
"Do not be afraid to make a commitment to another person," he said.