ויקרא, פרק י״ח, פסוק ו׳

At the foundation of family and marital life, clear boundaries elevate humanity above raw natural instincts, infusing everyday relationships with holiness. The laws governing forbidden relationships begin with an overarching rule before detailing specific cases. This structure teaches that these prohibitions are not subject to human logic or extrapolation. One cannot deduce new restrictions based on reasoning alone, such as forbidding an uncle to marry his niece simply because an aunt cannot marry her nephew. Only the relationships explicitly detailed in the Torah are forbidden [מלבי״ם, בכור שור, תולדות יצחק, הופמן].

The directive addresses all people, broadening its scope to teach that the nations of the world are bound by these laws just as the Israelites are [תורה תמימה, מלבי״ם, רבנו בחיי]. It emphasizes profound individual responsibility, calling upon every person to act with human dignity rather than corrupting their ways [תולדות יצחק]. It also introduces the vital boundary of seclusion, warning against even being alone with a forbidden relative [כלי יקר, פני דוד]. Because these laws hinge on willful participation, a man who is completely forced into a violation is exempt. Physical arousal requires conscious consent, and accountability falls only upon one who acts out of free choice [פני דוד, תיבת גמא].

Relatives are described as being of the same flesh, sharing an origin and remaining deeply connected to that original source [שד״ל, הופמן, ביאור יש״ר]. When the warning to avoid these forbidden bonds is issued, it addresses both men and women equally. Even though the man is typically the active initiator in the physical act while the woman is naturally more passive, both share equal responsibility and face the same consequences for the transgression [רש״י, מזרחי, גור אריה, שפתי חכמים, חזקוני].

A central discussion among commentators revolves around the exact boundary of the prohibition. One approach understands the warning against coming close as a literal ban on any affectionate contact that might lead to a physical union, such as hugging or kissing. Under this view, these preliminary actions are a severe violation in themselves [רמב״ם, כלי יקר, הכתב והקבלה, העמק דבר, תורה תמימה]. Conversely, another perspective views the concept of approaching simply as a polite euphemism for the marital act itself, meaning the core prohibition applies exclusively to the physical union [רמב״ן, שד״ל, חזקוני]. The act is described in terms of uncovering that which is private and meant to remain hidden [שד״ל, אבן עזרא], or as a profound physical bonding [ביאור יש״ר, הכתב והקבלה]. Regardless of whether the act is completed, the violation takes effect from the very first moment of physical initiation [רלב״ג].

Commentators explore multiple layers to understand why these specific bonds are forbidden. One approach focuses on controlling human urges. Since family members live in constant, close proximity, permitting these relationships would cause unchecked desire to overwhelm society [רמב״ם, רלב״ג, ספורנו]. Another perspective views this as a divine decree rooted in the deep secrets of human biology, noting that incestuous unions do not benefit human survival or produce healthy offspring, stemming purely from lust rather than the goal of reproduction [רמב״ן, טור הארוך, ספורנו, צאינה וראינה]. On a social and psychological level, marrying within the nuclear family would destroy the natural dynamics of respect, breed fierce jealousy, and distort foundational roles. By forcing individuals to marry outside their immediate circle, isolated families weave together to form a unified, cohesive nation [שד״ל, רש״ר הירש]. Mystically, relatives are seen as branches of a single original essence. Marrying a stranger unites separate branches back to a common root, whereas reuniting already connected relatives disrupts a deeper spiritual harmony [רבנו בחיי].

The laws conclude with a firm declaration of God's authority, serving as a promise that He faithfully rewards those who conquer their natural urges. Overcoming this temptation earns a reward equivalent to actively fulfilling a positive commandment [רש״י, מזרחי, גור אריה]. Ultimately, this serves as a reminder that even if the profound reasons behind these boundaries remain partially hidden from human understanding, they are the deliberate design of the Creator who knows the deepest secrets of His world [אבן עזרא, כלי יקר]. By honoring these boundaries, humanity emulates His holiness [הופמן].