Catechism of the Catholic Church §1641 — excerpt
"By reason of their state in life and of their order, [Christian spouses] have their own special gifts in the People of God." This grace proper to the sacrament of Matrimony is intended to perfect the couple's love and to strengthen their indissoluble unity.
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.
Also cites: LG 11 # 2 · LG 41