We Christians spend a great deal of time railing against what the Scriptures call sin. We are not alone. Orthodox members of Judaism and Islam do the same. Sin is a common theme in the Bible and the Quran. I cannot speak to what the Quran says specifically. I do not know the book all that well. However, both the Torah and the New Testament leave no stone unturned in defining what sin is. Both testaments, old and new are very specific, but it all comes down to one thing. Sin is anything that is in opposition to the will of God. Sin can be an overt act or it can be a failure to act. It is rebellion against the Lord God.
There was a time in human history when sin was undefined or poorly defined. People did not know what was expected of them by their Creator because He had not spoken His will for humanity and it was not written down. Right and wrong were dependent on the human conscience which, while created by God, was bent by environment, the need for survival and of course, sin. There was also the desire to empower our selves and control others through any means necessary to ensure comfort and safety in desperate times. Such was the nature and origins of what we now call sin. Even so, we did not recognize what it was until someone wrote it down. Control and sin have a special relationship. If we place the Creator in control, sin becomes less common. When we place ourselves in control, sin becomes rampant. Violence increases. Hate and fear rule the day. This is why human law, even when it is based on God's law, fails to do what was intended. We are still giving ourselves the control, ignoring our Creator, refusing to recognize Him as God.
It is the character of God that defines sin. We are told by all three Abrahamic faiths that God hates sin or anything contrary to His character. In ancient times, those that were called by God to serve Him were those men and women whose hearts were pure enough to serve. Even so, they were imperfect and fell into sin themselves from time to time. Since the choices made in Eden, humanity and all creation have been bent and distorted by the effects of sin. The process continues to this day. The difference is that we know what sin is and we do it anyway.
Adam and Eve knew what sin was in their garden. God told them. There was one thing they were to avoid. One thing that they were not to do. They did it anyway and forever fogged the lens through which we see righteousness. God could walk with us no longer. Our negative choices separated us from our Creator. As the world population grew, that separation became more and more evident.
Eventually God started over again. He allowed the line of Cain to perish in the great deluge that is recorded in every civilization on earth and is recorded in the Bible. He preserved a remnant of the Sons of God, the line of Seth. This was Noah and his family, bit the corruption from Adam was also in their gene pool too. The propensity to sin was still strong. It became evident immediately after their exit from the ark. Noah's son, Ham was particularly afflicted. The result was that the world again fell into sin. Humanity again reached out to overthrow their Creator on the Plain of Shinar with the Tower of Babel. This plan was filed again by the Lord. He confused their language so that the peoples of earth could not unite as one and so they scattered across the planet.
In the fullness of time, God called one man from Ur of the Chaldees to bear the gene pool that would ultimately bring the Hope of the world. This man was Abraham (initially called Abram). Abraham was not a sinless man, but he was a man of faith. Sometimes he failed in this regard, but God knew his heart and so blessed him as the progenitor of a new race - the Hebrews. Through his son, Isaac and his grandson, Jacob, the nation of Israel would be born. Among them, a man named Moses would rise to God's favor and become a leader of his people and it is through Moses that God gave His Law to the Hebrews and the world.
It is law that makes us aware that there is something wrong. It is law that condemns some behaviors and lifts up others. It is law that exonerates and executes. It is law that determines and defines civilization. Moses brought God's law.
Since God's law made sin apparent and made God's perfect character apparent, it showed everyone that no one was without sin. It showed the need for repentance and change of the human character. It showed the need for a relationship with other people and with God that was different from what had been. We must love God and love our neighbors if we wish to live in peace with our Creator and the world at large.
In a short time though, this view became lost and left unpracticed. It was replaced by the rote ceremonies to forgive sin and allow the people to do as they pleased. God wanted the peoples obedience, love and mercy. What He got was lip service and sacrifice. The law did not change hearts. It only condemned sinners.
What was needed was a sacrifice that would seal this breach, allow god to again dwell with His people and change their hearts.
So again, in the fullness of time, God raised up another prophet, but this one was different from any that had gone before. His Name was Jesus and He was God's very own Son. He came to teach the people and eventually the world through His legacy about His Father, about Sin and about entering into relationship again with God. For this, they crucified Him, but this was not unexpected. It was part of the plan, for in this act, the sins of humanity were paid for in full and God could now come in His Spirit to dwell with His people again - those that chose the path of faith.
It continues to this day in His Church - The Kingdom of God.