The birth of a fifth son brings a profound sense of divine validation to a mother navigating a deeply complex family dynamic. Rather than viewing the child's arrival as a mere natural occurrence, Leah recognizes it as the direct intervention and providence of God, a clear reward for her past sacrifices.
When she names her son, she openly declares that God has granted her a reward for giving her maidservant to her husband [רד״ק, The Torah]. The commentators explore why this specific act earned such a significant divine response. Rachel had given her maidservant out of the desperate necessity of barrenness. Leah, however, already had several sons. Handing her maidservant over to her husband was therefore an act of pure, selfless kindness [ריב״א, חזקוני]. Furthermore, this action reveals her deepest spiritual motives. The mothers of the family knew through prophecy that twelve tribes would eventually be established. By offering her maidservant, Leah sought only to increase her role in building these tribes for the sake of heaven, completely devoid of physical desire [ברכת אשר, חתם סופר].
God saw her sincere efforts and orchestrated events so that her eldest son would find mandrakes in the field. This discovery prompted Rachel to trade a night with their husband in exchange for the flowers. Through this chain of events, Leah was able to conceive again, receiving a direct reward for her righteous intentions [ביאור יש״ר].
The dual nature of this background is embedded in the child's name, Issachar, which is spelled uniquely in the original Hebrew with a repeating letter. The primary approach among commentators is that these two letters symbolize two distinct rewards. One represents the reward for giving her maidservant, and the other represents the reward of the mandrakes, through which she had essentially hired her husband for the night.
Although the name is spelled with two identical letters, only the first is pronounced while the second remains silent [מנחת שי]. Commentators offer various conceptual explanations for this silenced letter. One perspective suggests that Leah originally intended to name him after the act of hiring her husband with the mandrakes, but she corrected herself to emphasize the much more honorable act of giving her maidservant [שד״ל, שטיינזלץ]. The unpronounced letter thus represents the reward of the mandrakes. It remains silent because there is a lack of dignity in explicitly stating that she paid for her husband's company [רשב״ם, ריב״א, הדר זקנים, דעת זקנים, חתם סופר], and keeping it quiet also prevents any offense to her sister [הטור הארוך].
Other commentators present a different historical reason for the silent letter. They explain that Issachar later transferred this extra letter to his own son. His son was originally given a name that was considered improper, partly because it was later associated with an idol. To correct this, Issachar took the unpronounced letter from his own name and added it to his son's name, thereby giving him a new, respectable identity [ריב״א, הדר זקנים, דעת זקנים, ברכת אשר].