Leviticus 21:7-9

Leviticus 21:7-9 (KJV)
7 They shall not take a wife that is a whore, or profane; neither shall they take a woman put away from her husband: for he is holy unto his God.
8 Thou shalt sanctify him therefore; for he offereth the bread of thy God: he shall be holy unto thee: for I the Lord, which sanctify you, am holy.
9 And the daughter of any priest, if she profane herself by playing the whore, she profaneth her father: she shall be burnt with fire.

Playing The Whore

To be sexually active before marriage is called fornication. This is playing the whore in our promiscuity, which God hates.