The Torah spells it out, however, there is a degree of mystery and complexity that must be unraveled.
וַיִּרְא֤וּ בְנֵי־הָֽאֱלֹקים֙ אֶת־בְּנ֣וֹת הָֽאָדָ֔ם כִּ֥י טֹבֹ֖ת הֵ֑נָּה וַיִּקְח֤וּ לָהֶם֙ נָשִׁ֔ים מִכֹּ֖ל אֲשֶׁ֥ר בָּחָֽרוּ
“And the judges saw that the daughters of Mankind were good and they (forcibly) took whichever women they wanted as wives.” (Bereishis 6:2).
Who exactly are these בְנֵי־הָֽאֱלֹקים֙?
In Midrash Rabbah the meaning of בְנֵי־הָֽאֱלֹקים֙ is unequivocal.
Rabbi Shimon ben Yochai* said that they were corrupt judges who used their power and influence in society to kidnap and sexually assault women. The Midrash says that they would prey on young women who were adorned for their wedding** as well as married women. God considered this to be such a vile and pervasive form of evil that, five verses later, God declared his intention to אֶמְחֶ֨ה אֶת־הָאָדָ֤ם אֲשֶׁר־בָּרָ֙אתִי֙ “to wipe out Mankind that I created” (ibid 6:7). Commentators cite other reasons as well but this was certainly paramount among them.
What else could בְנֵי־הָֽאֱלֹקים֙ mean?
There is a clear precedent for the word אֱלֹקם֙ to refer to judges in the Torah:
וְהִגִּישׁ֤וֹ אֲדֹנָיו֙ אֶל־הָ֣אֱלֹהִ֔ים “And his master shall take him before the (court) judges.” (Shemot 21:6)
עַ֚ד הָֽאֱלֹהִ֔ים יָבֹ֖א דְּבַר־שְׁנֵיהֶ֑ם “The two parties should approach the (court) judges.” (Shemot 22:8)
What is unusual in the Midrash is that Rabbi Shimon ben Yochai goes so far as to curse anyone who interprets the phrase (in Aramaic) according to its literal meaning בְּנֵי אֱלָקיָּא. “children of exalted one or children of God” (Bereishis Rabbah 26:5). Yet we have other collections of Midrash (Yalkut Shimoni and Midrash Tanchuma Buber) which take this phrase to mean angels, (metaphorically compared to “children of God.” It was angels who came down to earth and committed these heinous crimes.
Fallen angels in the Torah – fact or fiction?
According to the account in the Yalkut Shimoni (ילקוט שמעוני על התורה מ״ד), God was saddened when Mankind started worshiping idols. Two angels told God that their original objection to the creation of Mankind had proved correct. Namely, that mankind will descend into iniquity. God replied that angels would not fare any better if they were on earth facing the moral challenges that people face everyday. The angels offered to take this challenge. Upon descending to earth, the angels immediately succumbed to immoral behavior with women and preceded to sexually assault them. According to this interpretation, the relevant verse in the Torah would be read: “And the angels saw that the daughters of Mankind were good and they (forcibly) took whichever women they wanted as wives.” (ibid)
Obviously, both Midrashim cannot be taken literally. In fact, Midrash in general is primarily designed to deliver a moral lesson. Midrash Rabbah’s approach – that בְנֵי־הָֽאֱלֹקים֙ means judges – is grounded in the reality of how the word is used elsewhere in the Torah. What then would be the moral message of the Yalkut Shimoni which says that בְנֵי־הָֽאֱלֹקים֙ means angels? Perhaps the Midrash is providing a psychological insight into those who are consumed by power and influence. They feel they are above the law and may justify their victimization of others as something that is their right. They may even see their actions as good and holy – like angels they are not bound by the rules of mankind.
* It is no coincidence that this Torah concerning Rabbi Shimon ben Yochai is being presented a week before Lag Baomer
** This moral outrage is reminiscent of what was inflicted on the Jews during the occupation of the Greek Assyrians. There is a story in a minor Midrash collection called “Maaseh Chanukah.” It describes the origin of Matisyahu’s rebellion a little differently. On her wedding night Matisyahu’s daughter, Chana, was outraged by the brutal edict that every bride had to spend the first night with the Greek Governor, so she began to disrobe at her wedding. When people reacted to this brazen act she asked them a tough question. Why are you so shocked by the sight of me disrobing and not by the fact that, in a few hours, I must spend my first night of marriage with the Greek Governor? This is how Matisyahu’s rebellion began.