The sacrament of marriage is a divine institution given to men and women that they might be “cooperators with the love of God the Creator” (GS 50) and so attain their supernatural end (GS 48). The primary means of their cooperation are the love and support they give to one another, and the gift of life and education they give their children (GS 50). Married couples share their entire being with one another—their bodies, their “feeling and affectivity”, and their “aspiration of spirit and will” (Catechism 1643). Their lifelong commitment to one another “in good times and in bad”, and their concern to instill in their children “the fruits of the moral, spiritual, and supernatural life”  (Catechism 1653), make the couple a “reflection of God’s love”, the love he manifested first in his covenant with Israel (Catechism 1611) and then in very Son Jesus. St. Paul calls marriage “a great mystery”, because through it Christ’s sacrificial love for human beings is re-presented to every generation (Eph 5:21-33). The supernatural mission entrusted to couples far exceeds their human capacity, but success is eminently possible through the “fruit of Christ’s cross”, the miraculous grace given to spouses by which they “live marriage in the new dimension of the Reign of God” (Catechism 1615). God’s grace ensures more than simple perseverance; it engenders a “joyful gratitude” that gives “prophetic” witness in our age to the power of God and to the love he bears all people (Bl. Pope John Paul II, “The Family in the Modern World”, 52).