Kayin sinned egregiously, going down in history as the first murderer. He took the idyllic state of Gan Eden and transformed it into a killing field. What makes his deed all the more pernicious is the reason for the murder: jealousy. Instead of learning from Hevel’s act of offering a korban, sacrifice, from his choicest flocks, Kayin killed him. Envy does that to a person, blinding him from seeing what is usually a simple truth that could change his life. Instead, he kills the messenger.
Kayin realized too late that he acted disastrously, but he repented. Hashem accepted Kayin’s teshuvah, but punishment had to be meted out. It would take seven generations for this to be realized. It was in the time of Lemech, whose son, Tuval-Kayin, was an expert at refining and shaping tools and iron-cutting instruments. Rashi notes the “irony” of Tuval-Kayin’s profession, in that Kayin was the first murderer and his great-grandson made weapons for murderers. What Kayin had commenced as a result of unbridled envy, Tuval-Kayin elevated to abusive form.
One day, Tuval-Kayin took his blind father, Lemech, on a hunting trip. Seeing what he thought was an animal, Tuval-Kayin instructed his father to put an arrow in the quiver and release the bow. Sadly, the figure that he saw was not an animal, but his great-grandfather, Kayin. Thus, Hashem waited seven generations to punish Kayin with his own chosen method for doing away with a “problem.” Once again, it was family, his very own grandson, who killed him.
Why did Hashem wait seven generations to punish Kayin? Furthermore, Kayin never knew he was being punished. When the arrow struck its mark, he was dead. In “A Vort From Rav Pam,” Rabbi Sholom Smith cites the Rosh Hayeshivah who observes that Hashem is teaching us an important lesson. It was the beginning of time; people would sin. Some might even think they could get away with it. This is especially true when a number of years have elapsed since a sin was committed and nothing seems to have happened. The sinner begins to think he has gotten away scot-free.
Kayin’s tragedy dispels this notion from our minds. Seven generations went by. Kayin probably thought it was over and done with. Hashem informs us otherwise. What a person does has far-reaching effects – often far beyond his own lifespan. Certain character traits, behavior patterns, and personality disorders which might seem innocuous now, are often inherited and “enhanced” by one’s descendants and developed into full-scale character flaws that spawn all forms of evil.
As always, there is a positive flip-side. The same descendants may inherit one’s positive character traits, refining them for greater achievement in their avodas Hashem. In any event, the lesson is powerful: What we do “today” can have serious ramifications “tomorrow.”