Society, that gave him liberty to rule the family, rigidly required of him that such rule should be in the social interest, as that interest was then understood.
It was obviously for the interest of society that women should be chaste, in order not only that a man might know his own children but that the family line and inheritance should be preserved from insecurity.

A man's infidelity to the marriage vow might seem to do no perceptible harm if practised outside the family circle, but woe to him if he trespassed upon the family ownership of another man.
There might be more than one wife acknowledged as secondary in status or a mere concubine slave to help in domestic duties while giving pleasure to the head of the family, but there was early a social demand for one chief wife whose offspring should inherit the family power.

Although even in this fixed demand there were loopholes of "legal fiction of adoption" by which some favorite child not of the actual line of inheritance might be given the place of honor and control.

Again, if the father under the patriarchal system was the recognized economic master he was also legally held to the financial support of wife and child.

In the collective family life his obligation extended far through the line of kinship and of alliance by marriage, and to-day in many Oriental countries the father may be bound to poverty as the responsible support of a large company of dependent pensioners.