Where in the bible does it say that it is a sin to have sex before marriage?

I know its a sin, but I'd like to know where in the bible this is located.

I suppose the good behind this is the fact that waiting until marriage will aid in the prevention of unplanned pregnancy and the spread of std's.

1 Corinthians 6:18-20 & 1 Corinthians 7:1-2

"Flee fornication. Every sin that a man doeth is without the body; but he that committeth fornication sinneth against his own body. What? know ye not that your body is the temple of the Holy Ghost which is in you, which ye have of God, and ye are not your own? For ye are bought with a price: therefore glorify God in your body, and in your spirit, which are God's. Now concerning the things whereof ye wrote unto me: It is good for a man not to touch a woman. Nevertheless, to avoid fornication, let every man have his own wife, and let every woman have her own husband."

The biggest reason for not having sex before marriage is the bond that is created between the two people.

Oh, certainly you can proclaim that you are not so fragile as to let mere intercourse cause you to become somehow linked with your mate du jour, but, according to Christian doctrine, that would be the case.

As for proof, simply read half the questions in the romance/dating section. It's amazing how much more mentally complex a relationship becomes once you start rolling in the hay.

No, sex before marriage is sinful even if you love each other. Being in love doesn't alter the reality that the sexual act is outside of marriage, marriage being the ceremonial union of a man and woman in matrimony. Sex outside of marriage is called fornication and the Bible definitely condemns it.

Matt. 15:19-20, "For out of the heart come evil thoughts, murders, adulteries, fornications, thefts, false witness, slanders. 20 鈥淭hese are the things which defile the man."
Acts 15:29, "...that you abstain from things sacrificed to idols and from blood and from things strangled and from fornication; if you keep yourselves free from such things, you will do well."
1 Cor. 6:9-10, "Or do you not know that the unrighteous shall not inherit the kingdom of God? Do not be deceived; neither fornicators, nor idolaters, nor adulterers, nor effeminate, nor homosexuals, 10 nor thieves, nor the covetous, nor drunkards, nor revilers, nor swindlers, shall inherit the kingdom of God."
Heb. 13:4, "Let marriage be held in honor among all, and let the marriage bed be undefiled; for fornicators and adulterers God will judge."
So, very clearly fornication is condemned in scripture and there is no provision for it being acceptable just because someone loves each other. Besides if this couple is so much in love, then why don't they carry out what true love is and marry each other? True love is when you put another person first, not when you take from them. For a man and woman to engage in fornication is to declare that such love for the other person is more self centered, than other centered

Heb 13:4 Let marriage be honorable among all, and the marriage bed be without defilement, for God will judge fornicators and adulterers.

also read 1 Corinthians 6:12-20 and all of chapter 7.

Hebrews 13:4-Marriage is honourable in all, and the bed undefiled: but whoremongers and adulterers God will judge.

Unplanned pregnancies and STD's still exist within a marriage.

So that doesn't always work either.

Check passages that talk about "fornication".

It's called fornication and it's a sin.

I know what you're getting at, you're trying to say fornication is a sin.

http://www.dianedew.com/adulforn.htm

Chritians i don't know how to spell it.