403 Q. What is the meaning of the commandment not to marry within the third degree of kindred? A. The meaning of the commandment not to marry within the third degree of kindred is that no one is allowed to marry another within the third degree of blood relationship.
“Third Degree.” What relatives are in the third degree? Brother and sister are in the first degree; first cousins are in the second degree; second cousins are in the third degree. Therefore all who are second cousins or in nearer relationship cannot be married without a dispensation from the Church allowing them to do so. A dispensation granted by the Church is a permission to do something which its law forbids. Since it made the law, it can also dispense from the observance of it. The Church could not give permission to do anything that God’s law forbids. It could not, for example, give permission to a brother and sister to marry, because it is not alone the law of the Church but God’s law also that forbids that. But God’s law does not forbid first or second cousins to get married; but the Church’s law forbids it, and thus it can in special cases dispense from such laws. God’s law is called also the natural law. You must be very careful not to confound the marriage laws that the Church makes with the marriage laws that the State makes. When the State makes laws contrary to the laws of God or of the Church, you cannot obey such laws without committing grievous sin. For instance, the State allows divorce; it allows persons to marry again if the husband or wife has been sentenced to imprisonment for life; it does not recognize all the impediments to marriage laid down by the Church. Such laws as these Catholics cannot comply with; but when the State makes laws which regard only the civil effects of marriage, such as refer to the property of the husband or wife, the inheritance of the children, etc., laws, in a word, which are not opposed either to the laws of God or of His Church, then you may and must obey them; for the authorities of the government are our lawful superiors, and must be obeyed in all that is not sin. What we have said with regard to the marriage laws is true for all the rest. Thus the civil court might, on account of some technicality, free you legally from the payment of a debt; but that would not free you in conscience from paying what you justly owe. Again, the court might legally decide in your favor in an unjust suit; but that would not give you the right in conscience to keep what you have thus fraudulently or unjustly obtained.