Cain and Abel, sons of Adam and Eve, are the first pair of siblings described in the Torah. They had a rocky relationship that culminated in a heated quarrel, which ended with CainThe Torah's description of their life is brief and cryptic murdering his younger brother. Their story is recorded in Genesis,1 but aside from an account of their birth, their bringing an offering to G‑d, and Cain’s horrifying murder of Abel, the Torah’s description of their lives is brief and cryptic.

The commentators provide a much-needed backdrop against which the lives of Cain and Abel play out. Let us cull these commentaries and draw a detailed picture of those tumultuous days fresh after the creation of the world.

Early Days

Cain and Abel were born to Adam and Eve on the sixth day of creation, the day they themselves were created. In fact, they were born even before Adam and Eve sinned with the Tree of Knowledge.23 The Midrash relates that three miracles happened to Adam and Eve on that first day: they were created, Eve conceived immediately and she gave birth.4,5

Eve named her first son “Kayin” (Cain), saying, “I have acquired a man with G‑d,” linking the name to the word “kinyan,” which means “acquisition.” She meant that when G‑d created her and Adam, He alone created them, but with this child, she and her husband were partners with Him.6 Others translate her statement to mean that “this son will be acquired by G‑d,” i.e., he will belong to G‑d, for even after she died, he would serve Him.7

Eve conceived again and gave birth to a second son, whom they named “Hevel” (Abel), meaning “vapor” or “vanity.” Abel’s name expresses how everything un-G‑dly is nothingness. All earthy and physical pleasures are without value, mere vapor.8

Cain was born with a twin sister, and Abel with two. And although the Torah doesn’t state this explicitly, it is derived from the seemingly unnecessary use of the word “et” (“with”), written once at Cain’s birth and twice at Abel’s.9 They each married the sister born with them. (Although generally forbidden, G‑d permitted this union of siblings so that the world would become populated.10) They quarrelled over who would marry the other sister born with Abel, Cain claimed rights to her because he was older, and Abel argued that she was born with him. Some explain that this dispute was one of the factors that led to Cain killing Abel.11

A Sour Offering

One spring, on the 14th of Nissan, Adam told his sons that their descendants were going to offer sacrifices to G‑d on this day (the Paschal offering), and suggested they do the same.12 Others say that this happened on Shavuot, or on Rosh Hashanah.13 Cain, a farmer, collected a portion of second-rate produce and offered it up to G‑d, and Abel, a shepherd, brought an offering of his own in the form of a sheep.

G‑d accepted Abel’s offering, sending a fire from heaven to consume it, but ignored Cain’s. This was because Abel offered his finest sheep, whereas Cain offered inferior produce.

When Cain saw that G‑d ignored his offering, he became frustrated and angry. G‑d reprimanded him for his unjustified anger and measly offering, warning him that the evil inclination “crouches by the door,” waiting to be let in so it can cause a man to sin. He encouraged him to overcome his evil inclination and repent.

One opinion says that Cain offered flaxseed,14 which is actually a valuable item. According to this opinion, the problem with Cain was not that he did not offer his best, but rather his attitude was an issue. In fact, the Rebbe, Rabbi Menachem M. Schneerson, of righteous memory, explains that Abel, too, did not offer his finest.15 Abel could have brought cattle as an offering, which is more valuable thanCain found a scapegoat for his anger sheep. What happened was that Cain and Abel disagreed as to what exactly G‑d wanted for an offering. Abel felt that it didn’t matter what type of species he offered, as long as it was top quality. Therefore he did not bring from the best species of animal, but he did bring the best of his sheep. Cain, on the other hand, felt that G‑d wouldn’t care for the quality of the offering, so long as it was from the best species. Therefore, although he could have brought a better quality offering, he brought flaxseed, the best type of produce he had.16

Both points of view were justified, and neither was held accountable for his initial reasoning. However, when G‑d demonstrated that he preferred Abel's offering, indicating that his line of thinking was correct, Cain should have accepted the fact happily and brought a new offering in the correct manner. His sin was that he refused to admit he was wrong, instead growing angry and blaming others.

Cain found a scapegoat for his anger in his brother Abel. Instead of turning introspective and repenting, he developed a terrible hatred for his brother.

Sibling Rivalry

Shortly after the episode of the offerings,17 Cain met Abel in the field and they began quarreling. Our sages give us four possible reasons they argued:

  1. They argued over who would marry their other sister.18
  2. At this point, Cain and Abel were Adam’s only sons. And since Adam had separated from Eve after their sin as a form of repentance (they eventually got back together and had other children), they thought that they would eventually inherit and divide the world between them. They quarreled over who would inherit the spot where the Temple would be built.19
  3. Cain and Abel divided the world between them. Cain took all the land, and Abel took all the movable property. Cain said to Abel, “What are you doing walking on my land? You have no permission. Fly!” Abel responded, “What are you doing wearing my clothes? You have no permission. Take off your clothes!”20
  4. Cain argued that G‑d does not reward for good deeds or punish for evil, and that there is no World to Come. Abel disagreed and said that G‑d judges fairly, each person according to their actions, and also that in the World to Come G‑d rewards the righteous and punishes the wicked.21

The argument turned violent, and they began to hit each other. Abel, though younger, was stronger than his brother and pinned him to the ground. Cain started to plead for mercy: “How could you harm me? What will you say to G‑d? What will you say to our father? I am still your brother!” Abel had mercy and released him. Immediately Cain pounced on Abel and began beating him.

As to how Cain killed Abel, there are three opinions:

  1. Cain did not know how to kill Abel, for he did not know the place of the vital organs. So he began to beat him over his entire body, until finally Abel died.22
  2. Cain remembered how his father sacrificed an animal to G‑d by slitting its neck, so he did the same to Abel.23
  3. He bit him like a snake.24

Too Holy

An alternative explanation to the story is brought by Rabbi Schneur Zalman of Liadi (the Alter Rebbe). He explains that the source of Cain’s soul was incredibly high,In his understanding, nothing was better or worse infinitely higher than Abel’s. As a result, he did not see the world as having any value. In Cain’s worldview, there was G‑dliness and nothing else; the world and its particulars did not exist. Therefore, when he brought an offering to G‑d, he brought flax, because, as the Gemara explains, flax represents oneness, as only one stalk grows from each flaxseed. 25

Since Cain’s worldview was that the world did not exist, it followed that there was no such thing as good or bad flax. In his understanding, there was no such thing as better or worse physicality. Everything was simply G‑dliness. Therefore, he did not feel it necessary to bring the best quality flax for his offering. For Cain did not take the world into consideration, in his mind it simply did not exist.

Herein lay Cain’s mistake. G‑d created a world for a reason—so that we elevate it. And he wants us to relate to it as having this purpose. This means that we should not be looking for a way to escape the world, rather we must work with it, utilizing it to serve G‑d.26

Perhaps this also explains why Cain murdered Abel. When G‑d ignored Cain’ s offering and preferred Abel’s, Cain should have accepted that his path was wrong and corrected it. However, because Cain had ridden on the wave of G‑dliness his whole life, he never worked on himself, never elevated himself. And thus, when it came to a test of character, when Cain had to step up and admit he was wrong, he failed. When his evil inclination reared, he was unequipped to control it, never having bothered to work on himself, choosing rather to ignore it and live the easy life of pure G‑dliness.

This was the true problem with his flax offering and the philosophy that left him incapable of dealing with his inner evil.27

Aftermath

G‑d called out to Cain, asking him where his brother was, hoping Cain would admit to his sin and repent. Cain feigned ignorance and said arrogantly, “I do not know. Am I my brother's guardian?” G‑d lambasted Cain, telling him how the blood of all Abel’s future descendants calls out to Him, demanding retribution. Cain’s punishment was that he was to wander the earth, a nomad with no permanent home, and he struggle to work the land. Cain regretted his terrible deed and told G‑d that his sin was too great to bear, and that he was afraid that he would get killed.

There is a debate among the commentators whether Cain was truly remorseful and fully repented, or he was just paying lip service to G‑d.28 Whatever the case, G‑d assured Cain that no one would harm him and promised that whoever killed him would be cursed. Retribution would only come seven generations later. G‑d placed a sign on Cain so that everyone would know not to kill him.

There are various explanations as to what exactly this sign was:

  1. G‑d placed a letter of His holy name on Cain’s forehead.29
  2. Since people were created in the image of G‑d, animals were afraid of them. When Cain killed Abel, he lost his image of G‑d’s likeness, and the animals were no longer afraid of him. Therefore they came to avenge Abel. G‑d placing a mark on him means that G‑d restored to him this image, and thus the animals reverted back to fearing him, and did not harm him.30
  3. G‑d gave him a dog to accompany and protect him.31
  4. The sun would rise and set specifically for him, therefore everyone would know that G‑d forgave him and should not harm him32
  5. G‑d placed a horn on his forehead.33

Divine Retribution

Afterwards Cain moved to Nod, which means “wander,” the same place Adam had gone after he was exiled from the Garden of Eden. He had a son and named him Enoch. He then built a city and named it after his son.

Just as G‑d promised, Abel was avenged seven generationsAbel was avenged seven generations later later when Cain died at the hands of his descendant Lemech. One day, Lemech, who was blind, went hunting with his son, Tuval Kayin. Because Lemech was blind, his son would tell him where to aim his bow, and Lemech would shoot. Tuval Kayin noticed an animal moving in the forest. He directed his father and Lemech let an arrow fly, killing the beast. Approaching the “animal” Tuval Kayin realized, to his horror, that it was none other than Cain. When he told his father what he had just done, Lemech clapped his hands together in grief, mistakenly striking Tuval Kayin dead between his palms.34 According to the tradition that G‑d placed a horn on Cain’s head, it is understandable why Tuval Kayin mistook him for an animal.

Moving On

The Rebbe explains that we could learn a powerful lesson from Cain’s conduct after his sin. Many people who sin either refuse to admit it, or admit it but wallow in feelings of self-loathing and self-pity, unable to pick themselves up and move forward. After Cain killed Abel, the verse describes the birth of his child and how he built a city. Cain not only repented for his sin, but took action and did something beneficial. He knew that he had destroyed human life, so he resolved to increase it. First he had a son, and then he built a city, a place where people could thrive and live productively. This teaches us a powerful lesson. We must not let ourselves be dragged down by past wrongdoings, rather, we must harness our feelings of remorse and channel them into something productive.35