bad marriages

The Word for today:
Ezra 9, 10

The Jews had just returned from 70 years of captivity in Babylon.  They were sent there as judgment against all of their sins.  But far and away the most damaging of their sins was idolatry.

Idolatry is when you confuse God for a nothing:
We know that an idol has no real existence, and that  there is no God but one. (1 Corinthians 8:4)

God doesn't want us counting on and relying on a nothing, so he reserves special places in his Bible for emphatic warnings against idolatry.  Here is the First Commandment of the Old Testament:
I am the LORD your God, who brought you out of the land of Egypt, out of the house of slavery. You shall have no other gods before me.  (Exodus 20:2-3)
 
Here is the First Commandment of the New Testament:
Jesus said to him, "I am the way, and the truth, and the life. No one comes to the Father except through me."  (John 14:6)
 
You see, God can't save us if we choose to rely on somebody or something else.  The reason God can't save people who don't follow him is because he will not disregard their choices.  When he says he's one, and that there is no other way, he isn't being angry and mean, or narrow and exclusive.  He is trying to show us the way home.  He knows that if we try to take any other way home, we won't get there:
Enter through the narrow gate. For wide is the gate and broad is the road that leads to destruction, and many enter through it. But small is the gate and narrow the road that leads to life, and only a few find it.  (Matthew 7:13-14)

That's what's behind the prohibition against marrying foreigners, which we read about in the final chapters of Ezra. 

The prohibition is not ethnic. God doesn't say anywhere in the Bible that we should not marry persons because they are from another country.

The prohibition is not racial; God doesn't say anywhere in the Bible that we should not marry persons because they are of another race.

The prohibition is spiritual.  God is warning them that foreign marriages, which caused their idolatry and exile in the first place, will cause them to slide into idolatry again.

He wants them to walk out on bad marriages so that they don't walk out on him.