i guess my starting point here would be slightly odd unless you understand where i'm coming from. as far as i can tell, nearly all the laws around marriage are for the benefit and protection of everybody concerned, husband, wife and children. however, the technical term here translated as "adultery",
TiNAPh is not what the english term means. the hebrew term signifies literally "moving from one to the other" and, as the rashi commentary explains:
Adultery applies only [to relations] with a married woman, as it is said: "[And a man who commits adultery with the wife of a[nother] man, who commits adultery with the wife of his neighbor,] [both] the adulterer and the adulteress shall be put to death" (Lev. 20:10); [and it says,] “[You are] the adulterous wife, who, instead of her husband, takes strangers” (Ezek. 16:32). [In both these verses, the term “adultery” is used in reference to the extramarital relations of a married woman.]
b'shalom
bananabrain