"The Lord saw how bad the sins of man had become on the earth. All of the thoughts in his heart were always directed only toward what was evil. The Lord was very sad that he had made man on the earth. His heart was filled with pain. So the Lord said, "I created man on the earth. But I will wipe them out. I will destroy people and animals alike. I will also destroy the creatures that move along the ground and the birds of the air. I am very sad that I have made man." Genesis 6:5-7
Another problem with sin is illustrated in these verses. Sin degenerates.
Once a person or a group of people are contaminated by sin, unless they aggressively address the problem, repent of the sin and turn from it, their situation will degenerate. Sinful behavior never makes things better but is extremely destructive.
This 6th Chapter of Genesis illustrates how badly the culture had degenerated. People had become so confirmed in their sinfulness that God was grieved that He had ever created them.
That is bad!
The same creatures and creation that He had once pronounced "very good" had now become "very bad". What a shame! Sin had degenerated God's Creation to the point that some divine intervention was going to be necessary.
I have never known anyone who ever sinned their way into a better life. They may have gained power, prestige, position, or possessions as a result of their sinful behavior, but at the expense of their soul.
Sin can't be managed. Sin can't be controlled. Sin can't be tolerated because sin corrupts, destroys and dehumanizes.
No doubt you know someone who has spent a lifetime trapped in sinful behavior. Is that person a better person than they were several years ago when they began living sinfully? Is their character stronger? Are their attitudes more positive? Do they have more spiritual virtues? I'll bet your answers are emphatic, "no's"! That is because sin degenerates.
What began several generations earlier with just two people in a small act of disobedience had now degenerated to the point where God was offended by the rampant wide-spread evil that now infected the human race. God could no longer abide their evil and was about to destroy everything He had made.
God takes sin seriously because He understands the degenerative nature of sin. It was killing Him to see such sinfulness and it would literally kill His Son. He hates sin because He loves people and sin degenerates people's spiritual nature, their character, their judgment, their health, their morality and their happiness.
Sin separates, sin alienates, sin complicates, sin contaminates, and sin degenerates. Deal with sin before it does you in.