42 These parties, let it be noted, not fettered but adorned by the golden bond of the sacrament, not hampered but assisted, should strive with all their might to the end that their wedlock, not only through the power and symbolism of the sacrament, but also through their spirit and manner of life, may be and remain always the living image of that most fruitful union of Christ with the Church, which is to venerated as the sacred token of most perfect love.
Source: Casti Connubii (Vatican.va)