בראשית, פרק כ״ו, פסוק ח׳

After living in Gerar for an extended period under the guise of being brother and sister, Isaac and Rebekah’s carefully guarded secret is finally uncovered. The sheer passage of time, rather than a sudden mistake, sets the stage for their revelation. From Isaac's perspective, the quiet months and years brought a sense of security. Because no one had attempted to take Rebekah, his initial caution faded. He gradually stopped keeping a strict distance from her and allowed himself to act more naturally [רשב״ם, רש״י, מזרחי]. Conversely, from the perspective of the Philistine king, Abimelech, this same passage of time sparked suspicion. The king wondered why, if Rebekah were truly Isaac's sister, she had not been given to any man in marriage after so long. This lingering question prompted him to observe them more closely [כלי יקר, יריעות שלמה]. Additionally, surviving for such a long duration under a dangerous false identity—which could easily have led to his execution under local laws—serves as a testament to God's constant protection over Isaac [מלבי״ם].

Abimelech's subsequent observation of the couple is understood in a few ways. He may have intentionally watched them from the high vantage point of his palace [ביאור שטיינזלץ, ביאור יש״ר]. However, the primary approach among commentators addresses the difficulty of assuming the righteous Isaac would act immodestly in front of an open window. Therefore, the king's discovery was not a direct sighting, but a logical deduction. Isaac had closed and locked his window in the middle of the day to darken the room. When Abimelech noticed the sealed window during daylight hours, he immediately grasped its implication [ריב״א, לבוש האורה, הדר זקנים]. A more mystical approach suggests that the window was not physical at all; rather, Abimelech utilized witchcraft or astrology to uncover what Isaac was trying to hide [צרור המור, משכיל לדוד].

The truth becomes undeniable when Isaac is observed showing a level of affection, playfulness, and intimate closeness reserved exclusively for a husband and wife, as a modest person would never act this way with a sister [שד״ל, העמק דבר]. While some commentators maintain that this involved only hugging, kissing, and physical closeness [חזקוני, שד״ל], a prominent view asserts that they were engaging in actual marital relations [רש״י, רשב״ם, גור אריה].

This latter interpretation raises questions about how Isaac could engage in such intimacy during the daytime and during a period of famine, which is traditionally restricted. In response, commentators explain that Isaac maintained absolute modesty by darkening the room or covering himself with his prayer shawl. Furthermore, the extended period he had been forced to distance himself from his wife granted him leniency to be with her [טור הארוך, גור אריה, פענח רזא]. Regarding the famine, the restriction did not apply because the region of Gerar was completely unaffected by the food shortage, or because Isaac himself possessed abundant wealth and was not experiencing any personal suffering [מזרחי, ריב״א, פרדס יוסף].