Unity and Indissolubility
The two essential properties of marriage — unity (one man, one woman) and indissolubility (until death) — flow from God's design and Christ's love for the Church.
CCC 1643–1651
Key Points
The central teachings from this section of the Catechism.
Conjugal love involves a totality in which the spouses share everything — body and soul, joys and sorrows. This love demands unity and fidelity: a giving of self that is total, faithful, and exclusive until death.
The unity of marriage requires the equal personal dignity of husband and wife to be recognized. Polygamy is contrary to this equal dignity and to conjugal love, which is undivided and exclusive.
The deepest reason for the indissolubility of marriage is rooted in the fidelity of God to his covenant and of Christ to his Church. Through the sacrament, spouses are enabled to represent and witness to this divine faithfulness.
Certain situations may justify the physical separation of spouses. Civil divorce may be tolerated when it is the only way to ensure legal rights. The divorced and remarried are not excluded from the Church and should be encouraged to participate in its life.
From the Catechism
"Conjugal love involves a totality, in which all the elements of the person enter — appeal of the body and instinct, power of feeling and affectivity, aspiration of the spirit and of will. It aims at a deeply personal unity, a unity that, beyond union in one flesh, leads to forming one heart and soul."
— CCC 1643, quoting Familiaris Consortio 13
"By its very nature conjugal love requires the inviolable fidelity of the spouses. This is the consequence of the gift of themselves which they make to each other. Love seeks to be definitive; it cannot be an arrangement 'until further notice.'"
— CCC 1646
"It can seem difficult, even impossible, to bind oneself for life to another human being. This makes it all the more important to proclaim the Good News that God loves us with a definitive and irrevocable love."
— CCC 1648
Scripture
"Have you not read that he who made them from the beginning made them male and female, and said, 'For this reason a man shall leave his father and mother and be joined to his wife, and the two shall become one flesh'? So they are no longer two but one flesh. What therefore God has joined together, let not man put asunder."
"The Lord was witness to the covenant between you and the wife of your youth, to whom you have been faithless, though she is your companion and your wife by covenant. . . . So take heed to yourselves, and let none be faithless to the wife of his youth."
"I will betroth you to me for ever; I will betroth you to me in righteousness and in justice, in steadfast love and in mercy. I will betroth you to me in faithfulness; and you shall know the Lord."
Common Questions
Because Christ himself taught it. Jesus restored marriage to its original indissolubility as intended by God "from the beginning." The marriage bond images Christ's irrevocable love for the Church — a love that never gives up or walks away.
The Church recognizes that some situations (e.g., abuse, danger) may make living together practically impossible. In such cases, physical separation is legitimate. Civil divorce may be tolerated as the only practical way to secure certain legal rights, but it does not dissolve the marriage bond before God.
They are not excommunicated and remain part of the Church. Pastors and the community should show attentive solicitude, encouraging them to listen to the Word of God, attend Mass, persevere in prayer, and raise their children in the faith. They should explore whether an annulment might apply to their prior union.
Unity and indissolubility are not burdens laid on marriage but gifts that flow from God's own faithful love. When spouses live these properties, they become a living sign of Christ's unbreakable bond with the Church.