ויקרא, פרק ח׳, פסוק ט״ו

The inauguration of the Tabernacle marks a profound transition, transforming physical objects into a sacred space. At the center of this process is the altar, which requires both spiritual and practical preparation before it can fulfill its purpose in the sacrificial service.

During this seven-day period, Aaron and his sons are not yet trained for their duties. Instead, Moses steps into the role of the acting High Priest, performing every stage of the service himself [מלבי״ם, פירושי רד״צ הופמן]. His purpose is to carefully demonstrate the precise details of the work to Aaron. Much like a mother teaching her daughter how to manage a household before handing over the responsibility, Moses provides hands-on instruction to prepare his brother for his future role [תורה תמימה, ביאור יש״ר, אדרת אליהו].

As part of this preparation, Moses applies blood to all four corners of the altar, ensuring every side is covered to establish that a partial application is insufficient [פירושי רד״צ הופמן]. The primary approach among commentators is that this action does not cleanse the altar from standard impurity, but rather elevates it from a secular state into one of absolute holiness. The very act of placing the blood on the corners achieves this spiritual purification [רש״י, רמב״ן, מזרחי, דברי דוד]. Additionally, this process serves as a personal atonement for Aaron, clearing him of any incorrect guidance he might have provided in the past [העמק דבר].

Moses then disposes of the remaining blood at the base of the altar. He does not simply throw it; he pours it slowly and continuously. Driven by a deep love for the Commandment, he ensures the liquid flows calmly and steadily to its designated place rather than splashing carelessly [הכתב והקבלה].

Through this careful service, the altar becomes fully sanctified, permanently prepared to atone for the sins of the Israelites [רש״י, הטור הארוך, אבן עזרא]. Yet, a conceptual challenge arises: why does a physical structure like the altar need its own atonement? When the Israelites were initially asked to donate materials for the Tabernacle, some individuals pressured their neighbors to contribute. Consequently, certain gifts were given out of shame or social pressure rather than a willing heart, leaving these donations with a subtle trace of theft. Because God despises stolen property brought as an offering, the altar requires a special atonement to cleanse it from any flaw caused by forced generosity or items obtained without the owner's complete consent [רמב״ן, מלבי״ם, אדרת אליהו, הטור הארוך].