“We have broken faith with our God …” (v2). The survival of the small group of Jews who had returned to Israel depended on being a holy people, dedicated to God’s ways. Intermarrying with their pagan neighbors meant that their children would be raised in other religions, idolatry would return, and the Jews would cease to exist as a separate people. Therefore, while there was precedent for God-fearing spouses to be accepted (like Ruth and Rahab), all others were sent back to their original families (v19).
“The people wept bitterly” (v1). While the New Testament teaches patience rather than divorce (I Cor 7:13), God’s desire is still that families serve Him together, to save us from grief.