בראשית, פרק ל״ח, פסוק ל׳

The birth of Tamar's twins concludes a symbolic struggle for the birthright, embodying both natural forces and future history. After his brother unexpectedly emerges first, the second child is born with a bright red thread tied to his hand. This distinctive marker leads directly to his naming. The primary approach among commentators is that his name was inspired by the red thread itself. The brilliant red color resembles the sun as it rises in the morning or sets in the evening, painting the sky in vibrant hues. Historically, the root of this name is also connected to ancient words denoting light and a radiant glow [אם למקרא]. Alternatively, the name reflects the infant's actions during birth. Much like the sun hiding behind clouds only to rise again, the baby extended his hand, pulled it back out of sight, and finally emerged into the world [שד״ל].

This difference between the brothers reflects a deeper contrast, as the two parallel the sun and the moon. The child with the red thread represents the sun, which shines in a constant, uniform manner. His brother represents the moon, which constantly waxes and wanes. This lunar cycle perfectly symbolizes the future royal dynasty of David that would descend from him—a kingdom destined to experience eras of great prosperity and illumination alongside dark periods of decline and destruction [רבנו בחיי, גור אריה].

The specific focus on the baby's hand carries extensive meaning, especially since the hand is mentioned four distinct times during the birth narrative. Commentators agree that this repetition serves as a prophetic hint to a future descendant, Achan, who would unlawfully stretch out his hand to steal forbidden spoils during the time of Joshua. Opinions differ on the exact meaning of these four mentions. One approach suggests they represent four separate wars where this descendant committed theft, specifically the battles against Amalek, Sihon and Og, the Canaanites, and Jericho. Another perspective argues that the four mentions correspond to four specific items he stole: a Babylonian garment, two pieces of silver, and a wedge of gold [רש״י, מזרחי, שפתי חכמים ואחרים].

The early extension of the baby's hand ultimately symbolizes the future character of his tribe. It represents a force that reaches out to forcefully take what does not belong to it. This stands in sharp contrast to his brother, who symbolizes a king breaking through boundaries in a just and lawful manner [גור אריה]. Thus, the red thread does more than simply mark the child who was initially meant to be the firstborn; it serves as a lasting sign of the nature and future actions of his descendants.