The book of Genesis is the first book of the Old Testament of the Bible. Genesis means beginning, and true enough Genesis is centered around a lot of beginnings in the lives of people whose stories are among core themes in Christianity.
It features the creation of the world as we know it, the creation of the first man and woman, the first destruction of the world, the covenant God made with Abraham, and the lives of three of his most notable descendants: Isaac his son, Jacob who later became the of the land of Israel and Joseph who became a court official for the Pharaoh of Egypt.
It is centered around the events that took place in Shechem in Canaan. Jacob had just left Syria, and he moved in with his thirteen children: Reuben Simeon Levi Judah Issachar Zebulun Dan Naphtali Gad Asher Benjamin Joseph and his only girl child, Dinah. They camped at an area of land owned by the descendants of Hamor, the man who was the father of Shechem. Jacob built an altar for God there as was his habit.
However, the peaceful coexistence soon came to an end, and it was as a result of Dinah's mistake. Dinah went into the town to go and see how the women of that place lived. Unfortunately she was spotted by Shechem the son of Hamor who was the leader of the Hivites. He grabbed her and raped her, hence defiling her, an action which led to a catastrophic chain of events. The Bible cites that Shechem had feelings for her, so he made his feelings known to her and even asked his father's to make marriage arrangements for them.
This did not settle well with Sons of Jacob, and they arranged a plan to exact revenge on Shechem and his father So they tricked the Hivite males into performing circumcision, as they said they was the condition they had to fulfill before they would allow Dinah to be married to Shechem.
In the verse in question, we can see that Shechem convinced the other leaders of the city and all the men to be circumcised. Circumcision was a painful procedure, and knowing the men would still be in pain and unable to fight, Simeon and Levi attached the city and killed all the men. They also took animals and other valuables that they could find and dragged away the wives and children of that land.
Lessons to learn here are straightforward. Christians are encouraged not to be associated in a friendly manner with people who are not of the Lord, as this can bring destruction. Not only was Dinah defiled, she was never mentioned again in the Bible from that point.
It is as though she ceased to exist, as the defilement relieved her of ant significance she could have had. Also, be careful to watch your temper, which we can see in the lives of Simeon and Levi. The act of uncontrolled anger on their part forced Jacob and his household to leave the area, as they were in trouble with nearby occupants of the land.
Their act led Jacob to place a curse on them as he was blessing his sons on the verge of death.