Pope Leo XIII provided some important teachings in his Encyclical Rerum Novarum (“of new things” or “condition of labor”) on the natural origin of marriage and family life, an area in which he warns civil government intrusion would be “a great and pernicious error.” His warnings are particularly germane to recent governmental attempts to redefine marriage and family life as something other than that ordained by God.
“No human law can abolish the natural and original right of marriage, nor in any way limit the chief and principal purpose of marriage ordained by God’s authority from the beginning: ‘Increase and multiply.’ Hence we have the family, the ‘society’ of a man’s house – a society very small, one must admit, but none the less a true society, and one older than any State. Consequently, it has rights and duties peculiar to itself which are quite independent of the State.” (Paragraph 12)
“A family, no less than a State, is, as We have said, a true society, governed by an authority peculiar to itself, that is to say, by the authority of the father. Provided, therefore, the limits which are prescribed by the very purposes for which it exists be not transgressed, the family has at least equal rights with the State in the choice and pursuit of the things needful to its preservation and its just liberty. We say, ‘at least equal rights’; for, inasmuch as the domestic household is antecedent, as well in idea as in fact, to the gathering of men into a community, the family must necessarily have rights and duties which are prior to those of the community, and founded more immediately in nature. If the citizens, if the families on entering into association and fellowship, were to experience hindrance in a commonwealth instead of help, and were to find their rights attacked instead of being upheld, society would rightly be an object of detestation rather than of desire.” (Paragraph 13)
“The contention, then, that the civil government should at its option intrude into and exercise intimate control over the family and the household is a great and pernicious error.” (Paragraph 14)