The Mishna (Yevamot 2:9) in today’s daf (Yevamot 25a) informs us that if a man brings a Jewish divorce bill (get) from abroad and declares that it was written and signed in his presence, then that man may not marry the woman who was the intended receiver of the divorce bill. Similarly, if someone testifies that a married man has died, or if they testify that they themselves killed him, they may not marry the woman whose husband they have just declared to be dead.
In terms of the final teaching in the Mishna, Rambam explains in his commentary on the Mishna that while we follow the halachic principle of אין אדם משים את עצמו רשע – literally ‘a person cannot place himself as an evildoer’ – which is the Talmudic principle rejecting self-incriminating testimony and which means that we would not accept the testimony of someone who said that they killed someone, nevertheless, our Sages decreed that such a person may not marry the woman about whose husband they testified as this may inspire some men to kill the husbands of married women towards whom they are attracted.
For some commentaries – such as Rabbi Yitzchak Minkovsky in his ‘Keren Orah’ commentary on Yevamot 25a – the claim that this decree was established to prevent men from killing the husbands of married women to whom they are attracted is unnecessarily cynical. Instead, he explains that the Rambam should have simply said is that that our Sages made this decree due to the concern that people may lie.
Yet, while what the Rambam speaks about is deeply unsettling, this does not stop it being true, and while we may not like the fact that people can at times be lustful, vindictive and malicious, this itself does not stop people being lustful, vindictive and malicious.
Finding the healthy balance between what we’d like people to be like while knowing what some people can be like is not easy. But what the Rambam seems to be saying here is that when lives may be in danger, and when there is a likelihood that people – motivated by lust – will do harm, we need to be realistic about that possibility and, as a result, make it clear to all concerned that we will do whatever we can to frustrate those violent plans and block those intended immoral outcomes.