וַיֹּאמְר֑וּ הַכְזוֹנָ֕ה יַעֲשֶׂ֖ה אֶת־אֲחוֹתֵֽנוּ׃ (פ)
Sinabi nila: “Dapat bang ituring niya ang aming kapatid na babae na parang isang babaing nagbebenta ng aliw?”
Rashbam
בנותיכם תתנו ואת בנותינו תקחו לכם, the sons of Yaakov, on their part made intermarriage something that was in their honour, “i.e. to give and to take.” When Shechem and Chamor presented this proposal to their townspeople they reversed it to make it appear as if they were the ones bestowing honour, when they said: “we will take and we will give.” (verse 31) They did this in order to seduce their townsfolk to submit to circumcision.
Rabbeinu Bahya
נשיא בית אב לשמעוני, “prince of a father’s house of the Shimonites.” He was one of five such princes of the tribe of Shimon (Ibn Ezra). Concerning him Solomon said in Kohelet 10,8: “he who breaks down a wall will be bitten by a snake.” The ancestral father, Shimon, had killed the people of Shechem for treating his sister like a whore (Genesis 34,31) and now one of his descendants had himself become guilty of tearing down the wall of chaste sexual mores established and defended by his forebear (Tanchuma Pinchas 2).
Meiri
Noahides are obligated to establish courts of law in every district and in every city, just as Israel was commanded, so that they will have fixed courts to judge cases concerning these seven commandments and to admonish their people regarding them. Since they were commanded in this, if they see someone transgressing and do not judge him, they are all executed. This is the reason why the people of Shechem were liable to be killed—not because of sexual immorality, since the woman was unmarried, but because of theft. As it is stated, “Shall he treat our sister like a harlot?” (Genesis 34:31), and the great rabbinic authorities wrote in their commentaries that “like a harlot” means that he treated her as ownerless, meaning that he would not be liable for theft. Thus, Shechem was guilty of theft, and they saw and did not judge him. This is the opinion of the great commentators. However, some leading scholars of later generations dispute this, saying that the obligation to establish courts for Noahides is only a positive commandment, and when it is said that “their prohibition is their death penalty,” this does not apply to positive commandments. According to their opinion, the killing of the people of Shechem was unjustified, and this is why Jacob cursed them. However, in my view, the obligation to establish courts is included in the commandment of “justice,” which prohibits wrongdoing and violence, and thus it is a prohibition, not just a positive commandment. Jacob did not curse them for acting unjustly, but because he had made an agreement with them and wanted to maintain his word and their treaty, going beyond the strict letter of the law. A proof for my view is what is stated later, that a Gentile who rests on the Sabbath is liable for the death penalty, as it is written, “Day and night they shall not cease” (Genesis 8:22). The Talmud asks why this is not included among the seven commandments and answers that the list only includes prohibitions of inaction, whereas this is an active prohibition. The Talmud then questions why the obligation to establish courts is included, since it is an active commandment, and answers that it includes both an active and a passive prohibition, meaning preventing wrongdoing, as it is written, “You shall not commit injustice” (Leviticus 19:15). Any means that leads to enforcing justice is therefore included.