72 We may now consider another class of errors concerning conjugal faith. Every sin committed as regards the offspring becomes in some way a sin against conjugal faith, since both these blessings are essentially connected. However, we must mention briefly the sources of error and vice corresponding to those virtues which are demanded by conjugal faith, namely the chaste honor existing between man and wife, the due subjection of wife to husband, and the true love which binds both parties together.
Source: Casti Connubii (Vatican.va)