In the Catechism of the Catholic Church, paragraph 1601 gives us this description of marriage: “The matrimonial covenant, by which a man and a woman establish between themselves a partnership of the whole life, is by its nature ordered toward the good of the spouses and the procreation and education of offspring; this covenant between baptized persons has been raised by Christ the Lord to the dignity of a sacrament.” This description, which is also found in Code of Canon Law, canon 1055, provides a brief and comprehensive set of details that aid us in considering the history and origins of marriage and how it is sacramental.
As shown in the book of Genesis, God’s creative work was only finished after having made human beings, male and female, in His own image and likeness. The creation story of Genesis 2 expresses in God’s word that “It is not good for the man to be alone. I will make a helper suited to him” (Genesis 2:18). This simple acknowledgement forms the divine basis for the reality of marriage from which flows all of the goods of marriage: the intimate union shared between a man and women, the capacity and the call to generate life - sharing in God’s creative work, and the good of each person within the marriage and within the family. Though sin entered into creation, these gifts and blessings were not lost in sin, even though the consequences of sin have made living these blessings more difficult. What is clear in God’s creative plan is that God himself wills the presence of married life and married love – and that such is so good that it remains even in the midst of a fallen and sinful world.
In Jesus Christ, marriage is elevated to an even higher level – one that is even greater than what Adam and Eve shared before sin entered the world: that of being a sacrament. Acknowledging that Jesus’s first miracle (at the wedding at Cana) already points to value of marriage, this gift of God is confirmed in its goodness by, Jesus’ own preaching, as especially related in Matthew 19:4-9. Here, Jesus elevates marriage to a higher level than was known even in Jewish observance – as Jesus appeals to God’s plan in the beginning which never foresaw any legitimacy of divorce, stating that the two are no longer so, but are one such that “what God has joined together, no human being must separate” (Matthew 19:6). That God Himself is joining the man and woman together in marriage of itself portrays marriage as sacramental – as it is God who is accomplishing the work of uniting the couple as one.
In Ephesians 5:31-32, St. Paul further demonstrates the sacramentality of marriage both as God’s work, and also as that which points toward heaven, following the same reasoning of Genesis 2:24 that is also found in Matthew 19: “For this reason a man shall leave [his] father and [his] mother and be joined to his wife, and the two shall become one flesh.” St. Paul refers in the passage to a “great mystery” in speaking in reference to the Church, in order to show how marriage symbolizes the mystery of Jesus’s own love for His bride, the Church (which husbands are to imitate in giving, and wives are called to accept and receive, in imitation of the fidelity of the Church).
Accordingly, the presence of marriage between one man and one woman is firmly rooted in Christ Himself and in His saving works offered for His bride, the Church. This simple truth is the foundation upon which marriage in the Church has existed and remains.
For further reading: In the Catechism of the Catholic Church, paragraphs 1601-1620 introduce marriage as a sacrament, speaking of its history from the beginning of creation through the New Testament teachings on marriage as a sacrament.