Dating your sisters husbands brother
In the great mass of writings which we have of the Fathers of any note in the Church, there is no sanction given to such marriages; but, on the contrary, when the Fathers have occasion to mention anything about such a union, they distinctly say that it is their custom, and that of the Church, not to consider such marriages as legal by the Word of God. Basil in the fourth century says, "Our custom has the force of law, because it has been handed down to us, i.e.
Consequently, when God says that man shall not marry any near of kin to him, He also, by even commencing with the marriage not to be contracted by woman, declares that equally woman may not marry any near of kin to her. God, then, says, "A man may not marry his mother." He lays down this rule, which is reasonable, that a woman may not do what a man is forbidden to do in like things.Now, by marriage, she is your aunt, and as such, like your father's sister, in No. Surely, now, these are the same for the woman, She cannot marry her uncle, either by blood or affinity.Her aunt's husband is as much her uncle by marriage as her father or mother's brother is by blood.As it seems probable that no efforts will be spared on the part of many people in this country to make it a law of the land that a man may marry his deceased wife's sister, it is incumbent on all who fear God to know what His law is on the subject. The one is made by man, the other by God, which is immutable.Therefore, if it be the law of God that "a man shall not marry his deceased wife's sister," it is not a question for debate at all.But, it is idle to talk of it being allowable for a man to marry his deceased wife's sister, when that sister is strictly forbidden by the law of God to marry him.
God, then, distinctly states that a woman may not marry her sister's husband.
The case I refer to was that of Leopold, King of Portugal, whose family was extinct in the next generation.
To this day the Roman division of the Western portion of the Church has to give a dispensation for this kind of marriage, which proves that it holds such a marriage to be illegal.
Consequently, whether the relationship be by kindred or affinity, in God's sight it is reckoned as kinship by virtue of the marriage.
In the first forbidden marriage, it is stated that a woman shall not uncover the nakedness of her father so that this expression is equally applicable to marriage of woman with man as it is to man with woman.
He starts us with one case for man and woman, thus— ∴ A woman may not marry her father.