Pope Francis stressed the importance of the natural family Monday, insisting it is based on the marriage between one man and one woman.

The pope was visiting the Catholic Shrine of Loreto, a pilgrimage site believed by many to contain the walls of the house of the Virgin Mary from Nazareth. “Indeed, here are conserved the walls that, according to tradition, come from Nazareth, where the Holy Virgin pronounced her ‘yes,’ becoming the mother of Jesus,” the pontiff noted in his address.

The house of Mary is “the house of the family,” Francis said. “In the delicate situation of today’s world, the family based on the marriage between a man and a woman assumes an essential importance and mission.”

“It is necessary to rediscover the plan drawn up by God for the family, to reiterate its greatness and irreplaceability in the service of life and of society,” he continued. “In the house of Nazareth, Mary lived the multiplicity of family relations as daughter, betrothed, wife and mother. For this reason every family, in its different members, finds here acceptance and inspiration to live its own identity.”

In the past, the pope has insisted that the natural family is under attack from “gender ideology,” which seeks to blur essential differences between men and women.

Gender confusion “contradicts the plan of God, who has entrusted the world and history to the alliance between man and woman,” the pope said during a 2016 address.

By its very nature, he said, this alliance requires the ability to recognize sexual differences “as a richness and a promise, not as a reason of subjection and abuse.”

“At the current juncture, marital and family ties are tested in many ways,” he added.

The Catechism of the Catholic Church underscores the nature of the family as founded on the marriage between a man and a woman.

“A man and a woman united in marriage, together with their children, form a family,” it reads. “This institution is prior to any recognition by public authority, which has an obligation to recognize it. It should be considered the normal reference point by which the different forms of family relationship are to be evaluated.”

The pope’s words in defense of the natural family come just days before the celebration of the World Congress of Families XIII, which will begin this Friday in the northern Italian city of Verona. Bringing together leaders and influencers from around the world, the Congress upholds the enduring importance of the natural family for the future of civilization.

The town of Loreto “lends itself to becoming, for the Church that is in Italy, a place to propose a continuation of the world meetings of young people and of the family,” Francis said Monday. “Indeed, it is necessary for the enthusiasm of the preparation and celebration of these events to correspond to their pastoral implementation, which gives flesh to the richness of the contact, through proposals for deepening, prayer and sharing.”

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