ויקרא, פרק ט״ו, פסוק י״ח

Marital intimacy introduces a specific state of ritual impurity for both a man and a woman. While the impurity of a man resulting from a seminal emission is established earlier, the primary focus here shifts to the woman [ביאור יש״ר, רד צ הופמן]. Unlike a man, who can contract impurity from various bodily discharges, a woman does not become impure from regular, non-blood secretions, but specifically as a result of intimate relations [ספורנו].

The primary approach among commentators is that the woman's impurity in this context does not stem from actual physical contact with the seed. According to standard law, internal contact within the body's hidden cavities does not transfer ritual impurity. Therefore, her impure state is understood as a unique divine decree from God. The very act of intimacy itself brings about this status, even if there is no external physical contact with the emission.

Several specific conditions govern this law. It applies only when the individuals reach a certain maturity; a female must be at least three years and a day old, and a male at least nine years and a day old [תורה תמימה, רלב״ג, אדרת אליהו, אור החיים]. The rule remains in effect regardless of whether the partner is a husband or a stranger [העמק דבר]. Furthermore, the impurity is triggered only by natural relations; unnatural intimacy does not render the woman impure, as it falls outside the standard definition of the act [תורה תמימה, רלב״ג, אדרת אליהו, אור החיים].

The presence of a viable emission is also strictly required. Penetration without a seminal emission does not cause this specific impurity, nor does an emission that has spoiled and lost its potential for fertilization [תורה תמימה, רלב״ג, חזקוני, אדרת אליהו]. However, if viable, moist fluid later exits the woman's body, she then becomes impure due to the external physical contact [רלב״ג, רד צ הופמן].

Because both individuals are active participants in the act, they both contract impurity and are required to immerse in water to purify themselves [ביאור שטיינזלץ]. The shared requirement for bathing serves to equate the woman's purification process with that of the man, meaning she must also follow standard immersion rules, such as dipping in a designated volume of water without any physical barriers on her body [אור החיים, חזקוני, אדרת אליהו]. Interestingly, unlike many other forms of ritual impurity, there is no requirement to wash one's clothing in this scenario, based on the logical assumption that garments would not be soiled during the act [פענח רזא, חומת אנך].