91 To conclude with the important words of Leo XIII, since the destruction of family life "and the loss of national wealth is brought about more by the corruption of morals than by anything else, it is easily seen that divorce, which is born of the perverted morals of a people, and leads, as experiment shows, to vicious habits in public and private life, is particularly opposed to the well-being of the family and of the State. The serious nature of these evils will be the more clearly recognized, when we remember that, once divorce has been allowed, there will be no sufficient means of keeping it in check within any definite bounds. Great is the force of example, greater still that of lust; and with such incitements it cannot but happen that divorce and its consequent setting loose of the passions should spread daily and attack the souls of many like a contagious disease or a river bursting its banks and flooding the land."
Source: Casti Connubii (Vatican.va)