במדבר, פרק ג׳, פסוק א׳

As the focus shifts from the general census of the Israelites to the specific counting of the tribe of Levi, an immediate question arises regarding the leadership of the tribe. The narrative announces the lineage of both Aaron and Moses but subsequently lists only the sons of Aaron. The primary approach among commentators is that Aaron's sons were distinguished from the rest of the tribe because they were anointed for the priesthood, thereby earning a separate and prominent mention. In contrast, the sons of Moses remained regular Levites and are included later under the broader family grouping. The explicit absence of Moses's sons in this initial count highlights his immense humility, as he did not seek power, honor, or special titles for his descendants [שד״ל]. Furthermore, driven by absolute dedication to leading the public, Moses simply did not have the time to focus on nurturing his own biological sons [חתם סופר]. His personal greatness was so complete that he did not require the mention of his children to validate his legacy [צרור המור].

Since the biological sons of Moses are not named here, commentators agree that Aaron's sons are considered the offspring of Moses because he taught them Torah. A well-established principle dictates that anyone who teaches a friend's child Torah is considered to have fathered them [רש״י, רבנו בחיי]. However, since Moses taught the entire nation of Israel, one might wonder why only Aaron's sons are uniquely identified as his lineage. The answer lies in the exceptional effort Moses invested in them, far beyond his basic obligations. He taught them the Oral Torah in profound depth, dedicating special time to them and instilling within them a completely new spiritual essence [גור אריה, העמק דבר, שפתי כהן]. Another explanation for this unique relationship stems from their survival. Following the sin of the Golden Calf, a decree of destruction hung over Aaron's sons. Through his powerful prayers, Moses managed to save half of them, Eleazar and Ithamar. By effectively granting them their lives anew, they are considered his own children [כלי יקר].

The specific mention of the time when God spoke to Moses at Mount Sinai gives rise to two main perspectives. The historical approach points out that at Mount Sinai, before the Tabernacle was erected, Aaron had four living sons who were chosen for the priesthood. The narrative immortalizes this brief period when all four were alive, because later, upon the establishment of the Tabernacle, Nadab and Abihu died [רשב״ם, אבן עזרא, חזקוני]. Their tragic deaths serve as a stark reminder that God is exceptionally exacting with the righteous, showing no favoritism even to anointed priests who fall into sin [רבנו בחיי, צאינה וראינה]. Conversely, the educational approach views this timeframe as the very beginning of the spiritual bond between Moses and his nephews. From the exact day God spoke to Moses at Mount Sinai, Moses began imparting that divine knowledge to Aaron's sons, transforming them into his spiritual descendants [רש״י, מזרחי]. This process was not merely a one-way transfer of information but a collaborative study and deep analysis of the Oral Torah, achieved with Divine assistance [העמק דבר].