Nehemiah 13:24

Half of their children spoke the language of Ashdod or the language of one of the other peoples but could not speak Hebrew.

For I will then restore
pure speech to the peoples
so that all of them may call
on the name of Yahweh
and serve Him with a single purpose.

Treasury of Scripture Knowledge

And their children spake half in the speech of Ashdod, and could not speak in the Jews' language, but according to the language of each people.

For I will then restore
pure speech to the peoples
so that all of them may call
on the name of Yahweh
and serve Him with a single purpose.

Do not intermarry with them. Do not give your daughters to their sons or take their daughters for your sons,

The Israelites took their daughters as wives for themselves, gave their own daughters to their sons, and worshiped their gods.