Nehemiah 13:23

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

Nehemiah 10:30

and that we would not give our daughters to the peoples of the land, nor take their daughters for our sons:

Ezra 9:1-2

Now when these things were completed, the princes came to me, saying, The people of Israel, and the priests and the Levites, have not separated themselves from the peoples of the lands, according to their abominations, even of the Canaanites, the Hittites, the Perizzites, the Jebusites, the Ammonites, the Moabites, the Egyptians, and the Amorites;

Ezra 10:10

And Ezra the priest stood up and said to them, Ye have acted unfaithfully, and have taken foreign wives, to increase the trespass of Israel.

Nehemiah 13:1

On that day they read in the book of Moses in the audience of the people; and there was found written in it that the Ammonite and the Moabite should not come into the congregation of God for ever;

1 Samuel 5:1

And the Philistines took the ark of God, and brought it from Eben-ezer to Ashdod.

Ezra 9:11-12

which thou hast commanded by thy servants the prophets, saying, The land, unto which ye go to possess it, is an unclean land through the filthiness of the peoples of the lands, through their abominations with which they have filled it from one end to another through their uncleanness.

Ezra 10:44

All these had taken foreign wives; and there were among them wives who had had children.

Nehemiah 4:7

And it came to pass, when Sanballat, and Tobijah, and the Arabians, and the Ammonites, and the Ashdodites heard that the walls of Jerusalem were being repaired, that the breaches began to be stopped, then they were very wroth,

2 Corinthians 6:14

Be not diversely yoked with unbelievers; for what participation is there between righteousness and lawlessness? or what fellowship of light with darkness?

Treasury of Scripture Knowledge

Summary

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

Bible References

Married

Nehemiah 10:30
and that we would not give our daughters to the peoples of the land, nor take their daughters for our sons:
Ezra 9:2
for they have taken of their daughters for themselves and for their sons, and have mingled the holy seed with the peoples of the lands; and the hand of the princes and rulers has been chief in this unfaithfulness.
Ezra 10:10
And Ezra the priest stood up and said to them, Ye have acted unfaithfully, and have taken foreign wives, to increase the trespass of Israel.
2 Corinthians 6:14
Be not diversely yoked with unbelievers; for what participation is there between righteousness and lawlessness? or what fellowship of light with darkness?

Ammon

Nehemiah 13:1
On that day they read in the book of Moses in the audience of the people; and there was found written in it that the Ammonite and the Moabite should not come into the congregation of God for ever;

General references

Exodus 34:16
and thou take of their daughters unto thy sons, and their daughters go a whoring after their gods, and make thy sons go a whoring after their gods.
Deuteronomy 7:3
And thou shalt make no marriages with them: thy daughter thou shalt not give unto his son, nor take his daughter for thy son;
Judges 3:6
and they took their daughters to themselves for wives, and their own daughters they gave to their sons; and they served their gods.