Why Does God Forbid Pre-marital Sex

Accordingly, 50% of the people who currently have HIV are between the ages of 15 and 24 and this has been brought by pre-marital sex. Using a condom only reduces the risk of contracting HIV by 85% . Condoms do not significantly reduce the risk of contracting other sexually transmitted diseases. Premarital sexual activity can lead to taking virus, fungi, bacteria, yeast, spores, or parasitic contamination into the marriage bed once already committed to one partner. 

Gay and bisexual men of all races are the most severely affected by HIV. In 2012, there were 35.3 million (32.2 million–38.8 million) people living with HIV. Since the start of the epidemic around 75 million (63 million–89 million) have become infected with HIV. Premarital sex has been pointed as one of the culprits of AIDS multiplication.

Genesis 3:11 Then He asked, "Who told you that you were naked? You have eaten, then, from the tree of which I had forbidden you to eat!

Matthew 5:28 But I say to you, everyone who looks at a woman with lust has already committed adultery with her in his heart.

1 John 2:16 For all that is in the world, sensual lust, enticement for the eyes, and a pretentious life, is not from the Father but is from the world.

Divorce statistics are higher because of pre-premarital sex or lived together before deciding to marry. 

Galatians 5:16 say, then: live by the Spirit and you will certainly not gratify the desire of the flesh.

After engaging in premarital sex , many people express feelings of guilt, embarrassment, distrust, resentment, lack of respect, tension, etc..God does not want anyone to experience unnecessary emotional pain. 

Galatians 5:16 For the flesh has desires against the Spirit, and the Spirit against the flesh; these are opposed to each other, so that you may not do what you want.

Sex is not limited to married couples to rob pleasure from the unmarried. Premarital sex is forbidden to protect unmarried people from unwanted pregnancies, from children born to parents who do not want them, and to protect children from parents who are incapacitated because of unpreparedness.

Galatians 5:24 Now those who belong to Christ (Jesus) have crucified their flesh with its passions and desires.

On marital infidelity, the consequence is most likely unbearable: emotional trauma, blow to self-esteem,  distrust, disorientation, dented social life, financial struggle, deteriorating impact on family and children 

Exodus 20:17 "You shall not covet your neighbor's house. You shall not covet your neighbor's wife, nor his male or female slave, nor his ox or ass, nor anything else that belongs to him."

The Bible does not speak about the consequences of pre-marital but only provides us with pre-caution through Divinely Precepts because God gives us the freewill to establish our dependence and loyalty on Him in love, respect and fidelity...Amen!