Following the tragic deaths of Aaron's elder sons, the mantle of spiritual and practical leadership over the Levite service in the Tabernacle passed to Eleazar. As the deputy priest, he assumed the supreme responsibility of safeguarding the most sacred materials and orchestrating the transport of the holy vessels through the wilderness [אבן עזרא, ביאור שטיינזלץ].
Eleazar was personally appointed to oversee four vital components of the daily service: the lighting oil, the fragrant incense, the daily grain offering, and the anointing oil. The sheer holiness of these items demanded the exclusive supervision of someone of his elevated status [שפתי כהן, אם למקרא]. Furthermore, because these materials were continually depleted through daily use, they required meticulous oversight to ensure they were neither stolen nor diverted for secular purposes [שד״ל].
The logistical challenge of transporting these sacred materials during the wilderness journeys generated considerable discussion. One perspective suggests that Eleazar did not physically carry these items himself. Instead, he functioned as an executive officer, selecting particularly agile and pious men from the Kohathite clan and entrusting the burdens to them [רמב״ן, ספורנו, אבן עזרא, הטור הארוך, רלב״ג]. Conversely, a prominent tradition asserts that Eleazar bore the entire load personally. In this vivid depiction, he carried the lighting oil in his right hand, the incense in his left, balanced the daily grain offering on his arm, and suspended a flask of anointing oil from his belt. Given that the incense weighed hundreds of pounds and the oil amounted to dozens of liters, carrying such an overwhelming burden required either miraculous intervention or the extraordinary physical strength attributed to great biblical figures [רמב״ן, רבנו בחיי, תורה תמימה, צאינה וראינה, שפתי כהן, משכיל לדוד].
A middle approach draws a practical distinction between the materials. According to this view, Eleazar personally carried the oils and the incense, as they required complex preparation beforehand. However, he did not physically carry the fine flour of the daily grain offering while traveling. If the flour had been sanctified in a service vessel prior to the journey, it would have been instantly disqualified the moment it left the camp. Therefore, his responsibility regarding the grain offering was strictly managerial, ensuring it was prepared and offered the moment the Israelites made camp [רש״י, ריב״א, שפתי חכמים, מזרחי, ברטנורא, גור אריה].
Beyond these specific materials, Eleazar's authority encompassed the entirety of the Tabernacle and its contents. He served as the supreme overseer of the Kohathites, directing them on exactly how to dismantle, transport, and reassemble the holiest vessels [רש״י, ספורנו, רמב״ן, הטור הארוך]. His brother Ithamar managed the transport duties of the remaining Levite clans [רש״י, רמב״ן]. Ultimately, Eleazar's specific duties perfectly mirrored his broader jurisdiction. By being entrusted with the oil, the incense, and the grain offering, elements that symbolize spiritual illumination, profound devotion to God, and constant service, he was inherently placed in charge of the very essence of the Tabernacle. The physical vessels only acquired true meaning through the materials and daily rituals that breathed life into them, making Eleazar the guardian of the Tabernacle's living soul [רש ר הירש].