Clearly the New testament says no, and no more now than any Christian can have any sex outside of marriage now too, and Like it or not, but why?
(1 Cor 6:15 KJV) Know ye not that your bodies are the members of Christ? shall I then take the members of Christ, and make them the members of an harlot? God forbid. 16 What? know ye not that he which is joined to an harlot is one body? for two, saith he, shall be one flesh.
(2 Cor 6:14 KJV) Be ye not unequally yoked together with unbelievers: for what fellowship hath righteousness with unrighteousness? and what communion hath light with darkness? 15 And what concord hath Christ with Belial? or what part hath he that believeth with an infidel? 16 And what agreement hath the temple of God with idols? for ye are the temple of the living God; as God hath said, I will dwell in them, and walk in them; and I will be their God, and they shall be my people. 17 Wherefore come out from among them, and be ye separate, saith the Lord, and touch not the unclean thing; and I will receive you, 18 And will be a Father unto you, and ye shall be my sons and daughters, saith the Lord Almighty. 7:1 Having therefore these promises, dearly beloved, let us cleanse ourselves from all filthiness of the flesh and spirit, perfecting holiness in the fear of God.
(1 Cor 5:9 KJV) I wrote unto you in an epistle not to company with fornicators: 9 Know ye not that the unrighteous shall not inherit the kingdom of God? Be not deceived: neither fornicators, nor idolaters, nor adulterers, nor effeminate, nor abusers of themselves with mankind, 10 Nor thieves, nor covetous, nor drunkards, nor revilers, nor extortioners, shall inherit the kingdom of God.
It has been my own witness now too that every true Christian that disobeyed God and married an unchristian next ended in divorce anyway.
(1 Cor 10:21 KJV) Ye cannot drink the cup of the Lord, and the cup of devils: ye cannot be partakers of the Lord’s table, and of the table of devils.
(1 Cor 10:22 KJV) Do we provoke the Lord to jealousy? are we stronger than he?
(1 Cor 10:23 KJV) All things are lawful for me, but all things are not expedient: all things are lawful for me, but all things edify not.
2 Corinthians 6:14: Do not be yoked together with unbelievers. For what do righteousness and wickedness have in common? Or what fellowship can light have with darkness?
(1 Tim 5:14 KJV) I will therefore that the younger women marry, bear children, guide the house, give none occasion to the adversary to speak reproachfully.15 For some are already turned aside after Satan.
1 Corinthians 7:39 A woman is bound to her husband as long as he lives. But if her husband dies, she is free to marry anyone she wishes, but he must belong to the Lord.
Repentance is in order..
Matthew 5:28 “But I tell you that anyone who looks at a woman lustfully has already committed adultery with her in his heart.”
(1 Cor 10:8 KJV) Neither let us commit fornication, as some of them committed, and fell in one day three and twenty thousand.
Mark 7:21 “For from within, out of men’s hearts, come evil thoughts, sexual immorality, theft, murder, adultery,”
Marriage is the second most important decision anyone ever makes. And what was the most important? A career? No. The most important decision is to accept Jesus Christ as your Lord and Savior. In fact troubled relationships due to religious differences eventually tend to dissolve the marriage and so today, thousands of Christian men and women stand on the threshold of loneliness and discouragement because their husband or wife is not a Christian. http://www.ncfliving.org/bk_117_nonchristian1.php
“Do not intermarry with them, and don’t let your daughters and sons marry their sons and daughters. They will lead your young people away from me to worship other gods. Then the anger of the LORD will burn against you, and he will destroy you.” (Deuteronomy 7:3-4)
“Don’t team up with those who are unbelievers. How can goodness be a partner with wickedness? How can light live with darkness?” (2 Corinthians 6:14)
(Rom 13:9 KJV) For this, Thou shalt not commit adultery, Thou shalt not kill, Thou shalt not steal, Thou shalt not bear false witness, Thou shalt not covet; and if there be any other commandment, it is briefly comprehended in this saying, namely, Thou shalt love thy neighbour as thyself.
1 Cor 15:33 Do not be so deceived {and} misled! Evil companionships (communion, associations) corrupt {and} deprave good manners {and} morals {and} character.
Gal 6:7 Do not be deceived {and} deluded {and} misled; God will not allow Himself to be sneered at (scorned, disdained, or mocked by mere pretensions or professions, or by His precepts being set aside.) For whatever a man sows, that is (also) what he will reap. ( he can reap too what others have sowed now too)
2 Tim 3:13 But wicked men and imposters will go on from bad to worse, deceiving {and} leading astray others and being deceived {and} led astray themselves.
Deuteronomy 22:10 Do not plow with an ox and a donkey yoked together.
Linking side by side two different species of different height and gait, and making them pull together, would be an act of cruelty.
Leviticus 19:19 . . . Do not mate different kinds of animals. . . .
John 14:15, 21, 23-24 says: If you love me, you will obey what I command. … Whoever has my commands and obeys them, he is the one who loves me. He who loves me will be loved by my Father, and I too will love him and show myself to him. …. If anyone loves me, he will obey my teaching. My Father will love him, and we will come to him and make our home with him. He who does not love me will not obey my teaching. These words you hear are not my own; they belong to the Father who sent me.
see also
Focus on the Family 