Nehemiah 9:2
Those of Israelite descent separated themselves from all the foreigners, and they stood and confessed their sins and the iniquities of their fathers.

2 Chronicles 30:7-9
Do not be like your fathers and brothers who were unfaithful to the LORD, the God of their fathers, so that He made them an object of horror, as you can see. / Now do not stiffen your necks as your fathers did. Submit to the LORD and come to His sanctuary, which He has consecrated forever. Serve the LORD your God, so that His fierce anger will turn away from you. / For if you return to the LORD, your brothers and sons will receive mercy in the presence of their captors and will return to this land. For the LORD your God is gracious and merciful; He will not turn His face away from you if you return to Him.”

Deuteronomy 7:3-4
Do not intermarry with them. Do not give your daughters to their sons or take their daughters for your sons, / because they will turn your sons away from following Me to serve other gods. Then the anger of the LORD will burn against you, and He will swiftly destroy you.

Malachi 2:11
Judah has broken faith; an abomination has been committed in Israel and in Jerusalem. For Judah has profaned the LORD’s beloved sanctuary by marrying the daughter of a foreign god.

1 Kings 11:1-2
King Solomon, however, loved many foreign women along with the daughter of Pharaoh—women of Moab, Ammon, Edom, and Sidon, as well as Hittite women. / These women were from the nations about which the LORD had told the Israelites, “You must not intermarry with them, for surely they will turn your hearts after their gods.” Yet Solomon clung to these women in love.

Exodus 34:15-16
Do not make a covenant with the inhabitants of the land, for when they prostitute themselves to their gods and sacrifice to them, they will invite you, and you will eat their sacrifices. / And when you take some of their daughters as brides for your sons, their daughters will prostitute themselves to their gods and cause your sons to do the same.

Joshua 23:12-13
For if you turn away and cling to the rest of these nations that remain among you, and if you intermarry and associate with them, / know for sure that the LORD your God will no longer drive out these nations before you. Instead, they will become for you a snare and a trap, a scourge in your sides and thorns in your eyes, until you perish from this good land that the LORD your God has given you.

Judges 3:5-6
Thus the Israelites continued to live among the Canaanites, Hittites, Amorites, Perizzites, Hivites, and Jebusites. / And they took the daughters of these people in marriage, gave their own daughters to their sons, and served their gods.

Nehemiah 13:23-27
In those days I also saw Jews who had married women from Ashdod, Ammon, and Moab. / Half of their children spoke the language of Ashdod or of the other peoples, but could not speak the language of Judah. / I rebuked them and called down curses on them. I beat some of these men and pulled out their hair. Then I made them take an oath before God and said, “You must not give your daughters in marriage to their sons or take their daughters as wives for your sons or for yourselves! ...

2 Corinthians 6:14-17
Do not be unequally yoked with unbelievers. For what partnership can righteousness have with wickedness? Or what fellowship does light have with darkness? / What harmony is there between Christ and Belial? Or what does a believer have in common with an unbeliever? / What agreement can exist between the temple of God and idols? For we are the temple of the living God. As God has said: “I will dwell with them and walk among them, and I will be their God, and they will be My people.” ...

1 Corinthians 5:9-11
I wrote you in my letter not to associate with sexually immoral people. / I was not including the sexually immoral of this world, or the greedy and swindlers, or idolaters. In that case you would have to leave this world. / But now I am writing you not to associate with anyone who claims to be a brother but is sexually immoral or greedy, an idolater or a verbal abuser, a drunkard or a swindler. With such a man do not even eat.

1 Corinthians 7:12-14
To the rest I say this (I, not the Lord): If a brother has an unbelieving wife and she is willing to live with him, he must not divorce her. / And if a woman has an unbelieving husband and he is willing to live with her, she must not divorce him. / For the unbelieving husband is sanctified through his believing wife, and the unbelieving wife is sanctified through her believing husband. Otherwise your children would be unclean, but now they are holy.

Matthew 19:4-6
Jesus answered, “Have you not read that from the beginning the Creator ‘made them male and female,’ / and said, ‘For this reason a man will leave his father and mother and be united to his wife, and the two will become one flesh’? / So they are no longer two, but one flesh. Therefore what God has joined together, let man not separate.”

Romans 12:2
Do not be conformed to this world, but be transformed by the renewing of your mind. Then you will be able to test and approve what is the good, pleasing, and perfect will of God.

1 Peter 2:9-12
But you are a chosen people, a royal priesthood, a holy nation, a people for God’s own possession, to proclaim the virtues of Him who called you out of darkness into His marvelous light. / Once you were not a people, but now you are the people of God; once you had not received mercy, but now you have received mercy. / Beloved, I urge you, as foreigners and exiles, to abstain from the desires of the flesh, which war against your soul. ...