Song of Songs lays it out pretty well
Are you referring to the song of Solomon?
I have been told that I do not have the authority to judge a person guilty or not guilty, actually all children of God have been given this authority according to His Word. However, you can't use what you don't know you have and if you don't know how to use it you can cause serious damage.
When we become children of God, we are counted blameless because of the Blood of Jesus Christ. Not Guilty.
Just because we are children of God does not make us sin free. Guilty.
It is not for us to judge what is right or wrong in a persons life. God will deal with that persons sin according to His own plan for them. If someone is having sex before marriage it is not for me to judge them but maybe to point out to them a better way with the guidance of the Holy Spirit.
Is the person wrong or guilty? Yes. Is the person going to Hell because of it. No, Not Guilty by the blood of the Lamb. When Satan the accuser comes to accuse a brother or sister, Not Guilty. When God comes and points it out guilty, but without condemnation or judgement just Love that is beyond words.
If someone is having sex before marriage then they are Not Guilty by the Blood of the Lamb, but guilty by His Word. Is God dealing with that person about this paticular sin in their life at this time? Unless God tells us we don't know. Should we stone them by Bible beating them into compliance? No. For who among us has no sin?Should we help them recover from this sin? Yes, if God calls us to do so, or we have that paticular confidence. Should we proceed humbly knowing full well our own weaknesses? Should we badger someone about it? Should we try to put ourselves in their shoes and try to understand how they feel?
There are things way beyond our understanding. I know couples who have had sex before marriage, married and lived very Godly lives. Was it wrong? Yes. Did God make it right in the end? Yes. Does this justify the sin? No.
Do you know what it is like to struggle with something so intensly that it absorbs all of your energy? If you have no energy left, then what kind of a healthy relationship do you think you could build with God? Unless you've been there, you don't know. There are sins in my own life that I know of that I don't bother with because I know I can't. I trust Jesus to honor His word.
Thou shalt not kill, yet we go to war and kill. We kill each other and create divisions amongst ourselves for what?
Sex before marriage is definitely fornication if you are out being promiscuous to fulfill your own lustful desires. But what if you are commited to one mate and there is true love involved? Right reasons at the wrong time.
Bottom line is we are all going to fall flat on our face. Sex is one of those sins that is against the body and the soul. If you burn with lust marry. If you're having sex outside of marriage, repent of this by making your marriage legal before God and man. God will forgive you if you ask Him for it and the grace to get through it.
Can sex be wrong in marriage? Yes if you are selfish about it.
I hope and have prayed that this be helpful to the reader.