The soul also houses sin and demons. So, through fornication, you’re more inclined to commit the same sins, and contract the same demons your partners have. This is why God commanded Israel not to join with the foreign women. All the surrounding nations served false gods. With all false gods, there are demons behind them.

Those foreign women had joined their souls to these unclean spirits through worship. Therefore, to get involved with those foreign women would lead to the same. If you read any part of the old testament, you’ll see the results of the Israel’s rebellion. Demons are whole beings (corrupted personalities), not fragments of a soul. It’s enough to deal with your own demons, but to deal with someone else’s, along with their fragmented soul, becomes a huge problem.

So you can see why fornication is detrimental and why marrying the right person is so important. You can also understand why God says not to have sex with animals. Who wants to have a portion of the mind, will, and emotions of a beast in them? We should only join ourselves to that one person God has for us, and be joined with Jesus Christ through obedience. To join with any other group of people, outside of the Holy God, will bring serious consequences.

The physical side of sex.

We all know what goes on here: body fluids are exchanged and semen is transferred. The problem with fornication is that every person’s body is different, and through sexual contact, unique organisms meet. The body has to handle this encounter and adapt and/or destroy these different organisms.

Too many encounters with too many different people, and the body gets overwhelmed and infected. This is where STDs come from, and especially AIDS. A man’s semen shouldn’t be in another man’s body and a human shouldn’t have intercourse with an animal. The body’s response to this is, “Woe, what the hell is going on!” Therefore, HIV is born.