who are relatives not by blood but by marriage, are said to be "one flesh" which is equivalent to being "near of kin." Thus not only does Adam speak of Eve "this is flesh of my flesh," but adds, with regard to husband and wife generally—"Therefore "shall a man leave his father and his mother and shall cleave unto "his wife; and they shall be one flesh" Gen. ii. 23 and 24. Thus men and women are "near of kin," not by blood only, but also by marriage. Now surely a wife's sister is a near relative, a very near relative, by marriage; and if a man is forbidden to marry any who are near of kin, he is certainly, according to the general law, not at liberty to marry one who is so nearly related as his wife's sister. If it had been forbidden to marry some only who are near of kin, there might have been some room for doubt, but the prohibition is against all who are near of kin; assuredly, therefore, the law, forbids marriage with a wife's sister.
In the more particular interpretation of the law laid down in Leviticus—taking in connection the general principle with the specified instances—it may fairly be assumed that when marriage is expressly prohibited between relatives of a certain degree of nearnesss it is unlawful between relatives of an equally distant degree. Thus, although a man is not expressly forbidden to marry his own niece, this may fairly be inferred from the express prohibition of a man's marriage with his own aunt, who is an equally distant relative. In like manner, although there is no express prohibition against a man's marrying his daughter, the unlawfulness of this marriage may be inferred from the express prohibition of marriage with his mother, who is equally removed. This principle, in its application to the law of marriage, is admitted by Dr. Chalmers in the same posthumous work in which he says that Lev. xviii. 18 implies the liberty to marry a deceased wife's sister, as well as "a connivance at polygamy." In his "Readings" on Lev. xx. we find the following words: "On verse 19 let me remark, that a mother's "sister is not nearer of kin than a sister's daughter; nor is a father's "brother of nearer kin than a brother's daughter." In other words, an uncle or an aunt is not nearer than a niece. Dr. Chalmers mentions this evidently for the purpose of showing that although a man is not expressly forbidden to marry his niece, yet this is unlawful, because the niece is as near a relative as the aunt. Let this rule be applied to the case of a wife's sister. A woman is as nearly related to two brothers of a different family, as a man is to two sisters of a different family. It follow's by the rule, that as marriage is expressly forbidden between a woman and two brothers in succession, so it is unlawful between a man and two sisters in succession. The marriage of a woman with two brothers is expressly forbidden in Lev. xviii. 16 and Lev. xx. 21 "Thou shalt not uncover the nakedness of thy brother's wife, it is thy brother's nakedness." "If a man shall take his brother's wife it
