Sefer HaChinuch ספר החינוך

The commandment to burn one who is liable for burning: That the court burn with fire — meaning to say that the court is commanded to enact the statute of burning for some sins. And one of them is for the one that has sexual relations with a woman and her mother, as it is stated (Leviticus 20:14), “And a man that takes a woman and her mother — that is depravity — they shall be burned with fire, he and them, etc.” And I have already written above in the Order of Acharei Mot on the commandment not to have sexual relations with a woman and her daughter (Sefer HaChinukh 203), in which manner one who takes a woman and her daughter is liable, and that only one of them is included in the liability — and that is the last one. And [regarding] that which it is written, “and them (hen),” its understanding is “one of them.” As so does the explanation come in Tractate Sanhedrin 76b. And they said so there, that in [a certain] place they call one, “hen,” etc., as I have written there.

I have written above in Acharei Mot (Sefer HaChinukh 190) that which I have known and heard about the matter of the roots of the prohibition of forbidden sexual relations.

From the laws of the commandment is that which they, may their memory be blessed, said (Sanhedrin 52b) “The commandment of those that were burned is that they would submerge him in dung up to his knees, and they place a rough scarf within a soft one, and wrap [them] around his neck.” And his two witnesses, “this one pulls towards himself, and that one pulls towards himself, until he opens his mouth.” And they melt the tin or the lead or what is similar to it, “and [someone] throws it into his mouth, and it goes down and burns his intestines.” And the rest of its details are in the seventh chapter of Sanhedrin.

And this commandment is practiced by males, as judgment is for them; and only in the Land of Israel, as it is the place of judgment. And a court that transgresses it and did not judge someone liable according to this law has violated a positive commandment. And their punishment is great as the world is civilized by judgment. And I have already written on this positive commandment above in the Order of Mishpatim (Sefer HaChinukh 47) that Ramban, may his memory be blessed, does not count the four death penalties of the court in his tally of the commandments. And there I brought a little of the reason that he wrote about the matter.