The Torah in Parashat Re’eh discusses the procedure to be followed in the case of a Mesit – a person who attempts to convince his fellow to worship a foreign deity. It concludes by commanding, “Ve’lo Yosifu La’asot Ka’dabar Ha’ra Ha’zeh Mi’kirbecha” – “And they shall not again perpetrate this evil in your midst” (Debarim 13:12). This verse introduces the prohibition against being a Mesit – meaning, trying to persuade a fellow Jew to worship a foreign deity. This includes suggesting to a fellow Jew that they pray, bring incense, pour a wine libation, or bow to a foreign god. This transgression is violated even if the Mesit speaks in the singular form, saying, “I will go worship the deity,” subtly inviting his fellow to join him. Even if neither the Mesit nor the other person end up worshipping the foreign deity, the Mesit is guilty of violating this command through the attempt to persuade his fellow to serve a false god.
Halacha treats the Mesit with exceptional stringency, suspending some of the standard rules that normally apply with respect to trying and convicting suspected violators. For example, if a person tries to lure two people to worship an idol, those two people can then testify in court. Normally, only the testimony of objective third-party witnesses is accepted in Bet Din, but here, the two people whom the Mesit tried to lure may testify against him, and the Bet Din will convict and execute the Mesit on the basis of their testimony.
If the Mesit tries to lures just one person to worship an idol, then that person – who cannot testify alone, because Bet Din needs at least two witnesses to convict – has a Torah obligation to arrange for more witnesses. He does this by telling the Mesit that he has a friend who might be interested in idolatry, and then bringing his friend to the Mesit. After the Mesit seeks to lure both of them, the first person and his friend go to Bet Din and jointly testify against the Mesit. Or, if the Mesit does not wish to lure more than a single person, the person he approached must frame him by having two people hide and hear the Mesit attempt to lure him to foreign worship. They can then testify against him in court.
One who is found guilty of trying to lure someone to foreign worship is put to death. It is a Misva for the person whom he had tried to lure to participate in the execution.
The Sefer Ha’hinuch explains that it is due to the unique severity of this offense – missionizing, trying to lure Jews to foreign worship – that the Torah suspends the normal rules in order to ensure that the violator is convicted and punished.
This command applies in all places, at times when there is a court authorized to administer capital punishment, and to both men and women.
The Gemara teaches that causing a fellow Jew to sin is considered worse than killing him, as killing affects the body, whereas causing someone to sin affects his soul. For this reason, the Torah treats the Mesit – who seeks to lead his fellow away from the service of G-d, to foreign worship – with exceptional severity, in order to ensure that he receives his due punishment.