“I promise to be true to you in good times and in bad, in sickness and in health. I will love you and honor you all the days of my life.” This solemn declaration, pronounced by the bride and groom before the congregation as they give themselves to each other in the sacrament of matrimony, is a whole program in itself.
Marriage is a mission, and nurturing this love, cherishing it as one's most precious possession, is a long-term task that heralds the coming of the Kingdom of Heaven. Why, then, can we say that marriage too is an apostolate? The decree Apostolicam Actuositatem (On the Apostolate of the Laity) states that :
The Church was founded for the purpose of spreading the kingdom of Christ throughout the earth for the glory of God the Father, to enable all men to share in His saving redemption, and that through them the whole world might enter into a relationship with Christ. All activity of the Mystical Body directed to the attainment of this goal is called the apostolate, which the Church carries on in various ways through all her members. For the Christian vocation by its very nature is also a vocation to the apostolate.
Every baptized person has been called to spread the Good News, so that “everyone [may] be saved and [...] come to the knowledge of the truth” (1 Tim 2:4). How can we respond to this call within marriage?
Evangelizing the family
The man and woman who marry commit themselves to love and respect each other every day of their lives, to share joy and trials, to be faithful, and if God grants them children, to educate them in the faith. This work contributes to the spread of the Gospel, for both spouses must take care of their family to pass on the faith they have received to their children.
They do this first and foremost by giving them a good example, but also by catechizing them, since the family is the domestic Church (CCC 1655). The Church's dogmatic constitution Lumen Gentium specifies that, within the family, “parents should, by their word and example, be the first preachers of the faith to their children; they should encourage them in the vocation which is proper to each of them, fostering with special care vocation to a sacred state” (LG 11). In this way, spouses fulfill the mission entrusted by Christ to all the baptized, announcing to the world the salvation that comes from Christ and is the Church's raison d'être.