דברים, פרק ז׳, פסוק ג׳

To preserve its spiritual and national identity, a clear and rigid boundary is established between the Israelites and the surrounding nations. The most distinct expression of this separation is the absolute prohibition against intermarriage, which forbids forming family ties with them [ביאור שטיינזלץ]. Because Jewish law does not recognize the legal validity of a marriage between a Jew and a non-Jew, commentators grapple with how a prohibition can apply to a union that technically cannot exist. Two primary approaches address this dilemma. One perspective divides the commandment into two distinct scenarios. The first scenario addresses the seven Canaanite nations specifically after they have converted to Judaism. Although conversion typically permits marriage, these specific nations were so deeply entrenched in corruption that the restriction remained in place even after their conversion, a situation where the marriage would indeed be legally binding [רבנו בחיי, תורה תמימה, רש ר הירש]. The second scenario applies to these nations while they remain non-Jews [תורה תמימה, רש ר הירש]. Conversely, a second approach maintains that the entire prohibition deals strictly with non-Jews. Even without formal legal standing, it is entirely forbidden to form a permanent, exclusive romantic relationship that mimics marriage [העמק דבר, רלב״ג].

While biblical law focuses on permanent relationships, the Sages expanded this restriction to include casual encounters, preventing a gradual descent into intermarriage [תורה תמימה]. Historically, courts such as that of the Hasmoneans enacted severe decrees against these acts, and zealots are legally permitted to strike those caught committing them [רלב״ג, רש ר הירש]. Furthermore, the prohibition is not limited to the Canaanite nations. The underlying rationale extends it to any nation that might lead the Israelites toward idolatry [העמק דבר]. Despite the natural cultural divides between peoples, human nature inherently leans toward intermingling, necessitating an explicit warning [מלבי״ם]. The restriction also applies to those who facilitate these unions; acting as a matchmaker or an attendant for a non-Jew is forbidden, as it inherently praises and glorifies them [תורה תמימה]. Additionally, complex legal discussions exist regarding relationships with a Canaanite maidservant, whose status differs from that of a standard non-Jew [תיבת גמא, רלב״ג].

The central danger of these unions revolves around spiritual influence and lineage. Commentators emphasize the principle of matrilineal descent, where a child born to a non-Jewish woman shares her status. A person might harbor the illusion that their strong Jewish identity and family model will positively influence a non-Jewish spouse or son-in-law. In reality, it is the non-Jewish son-in-law who will eventually lead the Jewish grandchild astray into idolatry [רלב״ג, רש ר הירש]. The severity of this transgression is profound, carrying the penalty of premature death for one who marries a non-Jewish woman [העמק דבר].

Beyond the practical threat of idolatry, the prohibition carries a profound spiritual dimension. The bond between God and Israel is likened to the relationship between a groom and his bride. Introducing a non-Jewish partner into this intimate dynamic is compared to bringing a concubine into the King's palace. Such an act damages the holiness of Israel, siphons spiritual energy to forces of impurity, and ultimately leads to foreign nations dominating the Israelites [רקנאטי]. This severe, multi-dimensional restriction later served as the foundation for the biblical criticism of King Solomon, who was condemned for taking foreign wives [חזקוני].