For the unbelieving husband is made holy because of his wife, and the unbelieving wife is made holy because of her husband. Otherwise your children would be unclean, but as it is, they are holy. But if the unbelieving partner separates, let it be so. In such cases the brother or sister is not enslaved. God has called you to peace. 1 Corinthians 7:14-15
stacked paper: My Everyday December by Gina Jones
context:
To the rest I say (I, not the Lord) that if any brother has a wife who is an unbeliever, and she consents to live with him, he should not divorce her. If any woman has a husband who is an unbeliever, and he consents to live with her, she should not divorce him. For the unbelieving husband is made holy because of his wife, and the unbelieving wife is made holy because of her husband. Otherwise your children would be unclean, but as it is, they are holy. But if the unbelieving partner separates, let it be so. In such cases the brother or sister is not enslaved. God has called you to peace. For how do you know, wife, whether you will save your husband? Or how do you know, husband, whether you will save your wife? Only let each person lead the life that the Lord has assigned to him, and to which God has called him. This is my rule in all the churches. 1 Corinthians 7:10-17
related:
And this second thing you do. You cover the LORD’s altar with tears, with weeping and groaning because he no longer regards the offering or accepts it with favor from your hand. But you say, “Why does he not?” Because the LORD was witness between you and the wife of your youth, to whom you have been faithless, though she is your companion and your wife by covenant. Did he not make them one, with a portion of the Spirit in their union? And what was the one God seeking? Godly offspring. So guard yourselves in your spirit, and let none of you be faithless to the wife of your youth. “For the man who does not love his wife but divorces her, says the LORD, the God of Israel, covers his garment with violence, says the LORD of hosts. So guard yourselves in your spirit, and do not be faithless.” Malachi 2:13-16
A bit of clarification from an online commentary:
Any scruple which a Christian might have felt as to whether matrimonial union with an unbeliever would be defiling is here removed, and the purity of the former teaching justified. In contrast to that other union in which the connection is defiling (1Corinthians 6:16), the purity of the believing partner in this union, being a lawful one, as it were, entirely overweighs the impurity of the unbeliever, it being not a moral, but a kind of ceremonial impurity. The children of such marriages were considered to be holy fruit, so must we regard as holy the tree from which it springs.
I believe that the main point is that even though Christians are told not to be yoked with unbelievers (2Cor. 6:14), they don’t need to divorce their unbelieving spouse that they married before becoming a believer, nor to be troubled by the mistaken idea that the children of that marriage are somehow defiled because of the unbelieving parent. I’m sure the same applies to those who marry unbelievers while already being a believer, despite the fact that it goes against the Bible. God makes good of our mistakes, as shown in the following verse (16): “For how do you know, wife, whether you will save your husband? Or how do you know, husband, whether you will save your wife?” But nevertheless, a great deal of strife can be avoided by just doing as we’re instructed by the Bible in the first place.
It goes without saying that this is different from going against God’s entire design for male and female. No good will come out of that kind of relationship except upon repentance (turning away from it). God did not “make” some people to be attracted to others in such a way that He has said He abhors. He desires fruitfulness, which is not possible when [mis-]using body parts that were not made for that purpose. Anyone who says that is only for the Old Testament is (no doubt intentionally) ignoring a great many New Testament verses that speak clearly on the issue. Anyone who wants to argue about it should admit that their issue is ultimately with God, not with His children who are trying to be a light as He instructed them to be.
But sexual immorality and all impurity or covetousness must not even be named among you, as is proper among saints. Let there be no filthiness nor foolish talk nor crude joking, which are out of place, but instead let there be thanksgiving. For you may be sure of this, that everyone who is sexually immoral or impure, or who is covetous ( that is, an idolater), has no inheritance in the kingdom of Christ and God. Let no one deceive you with empty words, for because of these things the wrath of God comes upon the sons of disobedience. Therefore do not become partners with them; for at one time you were darkness, but now you are light in the Lord. Walk as children of light (for the fruit of light is found in all that is good and right and true), and try to discern what is pleasing to the Lord. Take no part in the unfruitful works of darkness, but instead expose them. For it is shameful even to speak of the things that they do in secret. But when anything is exposed by the light, it becomes visible, for anything that becomes visible is light. Therefore it says, “Awake, O sleeper, and arise from the dead, and Christ will shine on you.” Look carefully then how you walk, not as unwise but as wise, making the best use of the time, because the days are evil. Therefore do not be foolish, but understand what the will of the Lord is. And do not get drunk with wine, for that is debauchery, but be filled with the Spirit, addressing one another in psalms and hymns and spiritual songs, singing and making melody to the Lord with your heart, giving thanks always and for everything to God the Father in the name of our Lord Jesus Christ, submitting to one another out of reverence for Christ. Ephesians 5:3-21
It’s NOT “loving” to join in rebellion against God. Love is not the same thing as sex. You should indeed love everyone, but the Bible says that sex should only be between a man and his wife. Period. When searching out the truth for yourself, please avoid paraphrased “bibles” that that are deliberately twisted to make it appear that various sins are actually acceptable to God.