The first Mishnah in Massekhet Keritot lists the 36 Biblical sins that confer the penalty of karet. Almost half of them involve incestuous and adulterous sins, with the rest being connected with issues of desecration of God’s Name, violation of the major Jewish holidays and festivals, sins related to the Temple and the Temple service, and certain prohibitions regarding forbidden foods. In truth, there are other transgressions that also will bring about the penalty of karet, for example, the Gemara in Massekhet Shevu’ot (daf, or page 13) mentions someone who throws off the yoke of mitzvot, someone who rejects the traditional interpretation of the Torah and someone who violates the rite of circumcision. These are not mentioned in our Mishnah, since the individual who transgresses those commandments accidentally will not bring a sin-offering (since they are passive and do not involve an activity, and are not mentioned specifically in the Torah) and the focus of our Mishnah – and, indeed the entire tractate – is the atonement offered by means of the sacrifice to those who perform one of these sins unintentionally.
What is the penalty of karet?
According to the baraita in Massekhet Mo’ed Katan (daf 28a), both karet and mitah be-yedei Shamayim – a Heavenly death penalty – refer to a punishment in which the transgressor dies before his time. Someone liable to receive karet dies before he turns 50; someone liable to receive mitah be-yedei Shamayim dies before he turns 60. Other possibilities that appear there suggest that someone who receives karet will die suddenly or pass away without children. The Rambamargues that in the case of mitah be-yedei Shamayim the punishment ends with the person’s death, while the soul of someone who receives karet will suffer in the next world after death, as well.
Rashi points out that the punishment of karet applies only if the sin was done purposely without witnesses and proper warning. If there were witnesses who warned the individual that the action was forbidden, then the Jewish courts would try and punish the perpetrator according to the punishments that are appropriate for the act. Under some circumstances the sinner would receive lashes and would no longer be liable to receive the punishment of karet.