Exodus 34:16

And thou take of their daughters unto thy sons
That is, marry them to them, which explains what is meant by making a covenant with them, entering into such a near relation, and joining families, and thus intermixing with one another;

and their daughters go a whoring after their gods;
the worship of whom they have been trained up in from their infancy, and therefore hanker after them, and commit whoredom in a spiritual sense with them;

and make thy sons go a whoring after their gods;
by the means of tempting and drawing them into idolatrous practices, as the wives of Solomon were a snare to him.