שמות, פרק י״ט, פסוק ט״ו

Preparing for the Divine revelation at Mount Sinai requires a sharp transition from everyday life to a state of supreme holiness. This shift demands both a precise timeframe and a complete physical and spiritual separation.

Regarding the specific three-day preparation period, the primary approach among commentators is that the schedule refers directly to the third day itself [אבן עזרא, שד״ל, רלב״ג, חזקוני, ביאור יש״ר]. According to this view, Moses did not extend the timeline on his own; rather, the phrasing reflects standard biblical timekeeping. However, another perspective interprets the timeframe as a requirement to wait until the end of three full days [רש״י, העמק דבר, גור אריה, מזרחי, דברי דוד]. Following this line of thought, Moses independently added an extra day of preparation. He did so either because he understood that the people needed additional time to ready themselves or out of respect for the upcoming Sabbath, a decision with which God agreed.

To translate this call for sanctification into a practical directive, Moses instructed the men to separate from their wives [העמק דבר, קאסוטו]. The goal of this separation is to allow the people to focus, reflect, and mentally prepare for the historic event [ביאור שטיינזלץ]. Beyond mental readiness, there is a distinct legal reason concerning the ritual purity of the women. If couples were to engage in marital relations close to the giving of the Torah, a woman might experience a seminal discharge after her ritual immersion, thereby returning to a state of impurity. A three-day waiting period ensures that the seed loses its potency and no longer causes impurity, guaranteeing that the women can receive the Torah in absolute purity [רש״י, ריב״א, שפתי חכמים, תורה תמימה]. The nature of the restriction points to a specific, one-sided challenge. While a man can immerse and become pure immediately, the separation is primarily enforced for the sake of the woman, who strictly requires the full three-day wait to ensure her purity [מלבי״ם].

This raises a question as to why there is such strict attention to this specific impurity at Mount Sinai, especially when other severe impurities do not necessarily prevent engagement with Torah study. Commentators explain that impurity stemming from marital relations is associated with frivolity and physical pleasure. In contrast, standing before God to receive the Torah requires a state of awe, fear, and trembling. God's presence does not rest in an environment of frivolity [מזרחי, ריב״א, גור אריה, דברי דוד].

This directive had two long-term consequences. The first affected Moses himself. Drawing a logical conclusion from the temporary command given to the people, Moses reasoned that if the Israelites—whom God addressed only once—were required to separate from their wives for three days, then he, whom God might speak to at any given moment, must maintain complete and permanent separation. God agreed with this decision [תורה תמימה, ריב״א, פענח רזא]. The second consequence impacted the entire nation. Because the prohibition against marital relations was issued as a decree without an explicit expiration date, the restriction remained in effect even after the Torah was given. It lasted until God explicitly permitted the Israelites to resume normal relations by later telling them to return to their tents [הדר זקנים, בכור שור].