276. (5) Nevertheless, marriages in the world are to continue to the end of life. We cite this point to present more clearly to the sight of reason how necessary, useful and true it is that in marriages where conjugial love is not genuine, it should still be affected or be made to appear as though it were. It would be different if marriages once entered into were not compacts to the end of life, but could be dissolved at will. Such was the case in the Israelite nation, which arrogated to itself the right to put away their wives for any reason, as is apparent from this account in Matthew:
The Pharisees...came..., saying to (Jesus), "Is it lawful for a man to divorce his wife for any reason?"
Then when Jesus answered that it was not lawful to divorce a wife and marry another excepting for licentiousness, they replied that Moses had nevertheless commanded them to give her a certificate of divorce and put her away. And the disciples said,
"If such be the case of a man with his wife, it is better not to marry." (Matthew 19:3-10)
[2] Since the marriage covenant is accordingly a covenant for life, it follows that appearances of love and friendship between married partners are necessary. The principle that marriages once contracted are to continue on to the end of life in the world is based on Divine law, and being based on this, it is a matter also of rational law and therefore of civil law. It is based on the Divine law which says that it is not lawful to divorce a wife and marry another excepting on the grounds of licentiousness, as cited above. It is a matter of rational law, because rational law is founded on spiritual law, since the Divine law and rational law are the same. In the light of the one and the other together, or by considering the rational law in the light of the Divine law, it may appear to a great number of people what monstrous and destructive ruinations of society and dissolutions of marriages would result if divorcings of wives were at the good pleasure of husbands, prior to death. What monstrous and destructive ruinations of society would result may be seen in some measure in the narrative account in which the origin of conjugial love was discussed by the people gathered from the nine kingdoms, nos. 103-114, to which it is unnecessary to add further arguments. However, these considerations do not prevent separations from being permitted for their own reasons, as discussed above in nos. 252-254, and also the taking of a mistress, which we consider in Part Two.* * See "Taking a Mistress," nos. 462ff.