The birth of Judah's third son presents a notable break in the standard naming conventions of the era. Typically, parents alternated the responsibility of naming their children. The father would name the firstborn, the mother would name the second, and the pattern would repeat. Following this custom, Judah named his first son, and his wife named the second. Judah should have named the third child, yet it was his wife who gave the name. The primary approach among commentators is that she was forced to name the child herself because Judah was away in a place called Chezib during the delivery [רמב״ן, רלב״ג, דעת זקנים, חזקוני, ביאור שטיינזלץ, הטור הארוך, בכור שור, ביאור יש״ר].
The circumstances surrounding this birth were unusual in multiple ways. Regarding the pregnancy itself, the narrative simply states that she continued to give birth rather than noting a new conception. This suggests she did not conceive anew, but rather had been carrying twins, delivering the second and third sons consecutively [הטור הארוך]. As for Judah's absence, some explain he was in Chezib attempting to appease his brothers, who had excommunicated him following the sale of Joseph. It is suggested that this state of excommunication was the reason he had not merited raising worthy sons up to that point [פני דוד].
While Chezib is generally identified as a physical geographic location [אבן עזרא, רשב״ם, נתינה לגר, מחוקקי יהודה], many commentators find a deep thematic link between the name of the place and the name of the child, Shelah. Both names carry connotations of cessation, disappointment, or error. Specifically, Chezib implies a drying up or stopping, while Shelah relates to an ending, indicating that the mother stopped bearing children after this birth [רש״י, רא״ש, יריעות שלמה, חזקוני, דעת זקנים]. A chronological difficulty arises regarding how the location could be named after an end to childbearing, a fact that would only become apparent years later [רמב״ן]. Several resolutions are offered. The midwife may have noticed a physical complication during delivery that would prevent future pregnancies [העמק דבר], or clear signs of barrenness appeared immediately, turning the birth into a well-known event that gave the place its name [מזרחי, משכיל לדוד]. Alternatively, the names were not given with this foresight, but are instead interpreted retroactively based on how reality later unfolded [גור אריה].
The mother's choice of the name Shelah also reflects her personal emotional state. Disappointed that her husband was not by her side during labor, she selected a name rooted in illusion and letdown [ספורנו, שד״ל]. Since she bore the pain of childbirth entirely alone, the name can also be understood as meaning "hers," emphasizing that this child belonged to her solitary suffering, unlike the previous births where Judah was present [בכור שור]. On a deeper level, the concepts of error and deception embedded in both names serve as a subtle foreshadowing. They hint at the future chain of events involving Judah and Tamar, which would be fraught with mistakes and misdirection. Judah would eventually instruct Tamar to wait for Shelah to grow up but would fail to keep his promise, ultimately leading to his own error when he unknowingly encountered her on the road [הכתב והקבלה].