Deuteronomy 23:6

Thou shalt not seek their peace, nor their prosperity all thy days for ever.

Ezra 9:12

Now therefore give not your daughters to their sons, neither take their daughters to your sons, nor seek their peace or their wealth for ever: that ye may be strong, and eat the good of the land, and leave it for an inheritance to your children for ever.

2 Samuel 8:2

And he smote Moab, and measured them with a line, casting them down to the ground; even with two lines he measured to put to death, and with one full line to keep alive. And so the Moabites became David's servants, and brought gifts.

2 Samuel 12:31

And he brought forth the people that were in it, and put them under saws, and under harrows of iron, and under axes of iron, and made them pass through the brick-kiln: and thus he did to all the cities of the children of Ammon. So David and all the people returned to Jerusalem.

Nehemiah 13:23-25

In those days also I saw Jews that had married wives of Ashdod, of Ammon, and of Moab:

Treasury of Scripture Knowledge

Summary

Thou shalt not seek their peace nor their prosperity all thy days for ever.

Bible References

Thou shalt

2 Samuel 8:2
And he smote Moab, and measured them with a line, casting them down to the ground; even with two lines he measured to put to death, and with one full line to keep alive. And so the Moabites became David's servants, and brought gifts.
2 Samuel 12:31
And he brought forth the people that were in it, and put them under saws, and under harrows of iron, and under axes of iron, and made them pass through the brick-kiln: and thus he did to all the cities of the children of Ammon. So David and all the people returned to Jerusalem.
Ezra 9:12
Now therefore give not your daughters to their sons, neither take their daughters to your sons, nor seek their peace or their wealth for ever: that ye may be strong, and eat the good of the land, and leave it for an inheritance to your children for ever.
Nehemiah 13:23
In those days also I saw Jews that had married wives of Ashdod, of Ammon, and of Moab: