'And thou dost not join in marriage with them; thy daughter thou dost not give to his son, and his daughter thou dost not take to thy son,

Do not take wives or husbands from among them; do not give your daughters to their sons, or take their daughters for your sons.

And you shall not associate with them in marriage. You shall not give your daughter to his son, nor accept his daughter for your son.

Non junges te affinitate cum eis, filiam tuam non dabis filio ejus et filiam ejus non accipies filio tuo.

Neither shalt thou make marriages, etc. - The heart being naturally inclined to evil, there is more likelihood that the idolatrous wife should draw aside the believing husband, than that the believing husband should be able to bring over his idolatrous wife to the true faith.

Neither shalt thou make marriages with them,.... Unless they became proselytes, as Rahab, who was married by Salmon, and so those of other nations, as Ruth the Moabitess, and so any captive taken in war; otherwise it was not lawful, bad consequences have followed upon it, which it is the design of this law to prevent; that is, being snared and drawn aside into idolatry, which was the case of Solomon:
thy daughter thou shalt not give unto his son, nor his daughter shalt thou take unto thy son; for, according to the Targum of Jonathan, whosoever marries with them, it is as if he married with their idols: and this law, according to the Jewish writers (c), is binding with respect to other nations besides the seven; and whosoever marries any Heathen, of whatsoever nation, is to be beaten.
(c) Maimon. Hilchot lssure Biah, c. 12. sect. 1.