Preparing the altar for sacrifices in the future Temple requires a profound transition from an ordinary, secular state into a realm of holiness. This transformation is achieved through a unique dedication ceremony, where the application of sacrificial blood purifies the structure and prepares it for its sacred purpose.
The instruction to take the blood is directed personally to Ezekiel. He is tasked with receiving the blood in a vessel and sprinkling it. This specific command carries a profound promise from God. It ensures that Ezekiel will rise in the resurrection of the dead, physically whole and obligated in the commandments, so that he can wear the priestly garments and personally dedicate the future Temple [מלבי״ם].
The dedication process involves placing blood on several specific locations. First, it is applied to the four corners of the altar [רש״י, מצודת דוד, מלבי״ם]. Next, blood is applied to four surrounding corners. The primary approach among commentators is that this refers to the corners of the altar's roof, an area serving as a large ledge or border [רש״י, מצודת דוד, מלבי״ם, ביאור שטיינזלץ]. Alternatively, some suggest this refers to the actual courtyard standing directly in front of the altar [רד״ק], while others believe it points to the four corners of the Temple building itself [צאינה וראינה].
The final location for the blood is a surrounding border. Most commentators explain that this refers to the base of the altar, where the remaining blood is poured out, following the standard practice outlined in the Torah [מצודת דוד, ביאור שטיינזלץ]. Another perspective identifies this as a special protrusion on the altar itself [מלבי״ם], while a different view connects it back to the border of the previously mentioned courtyard [רד״ק].
The ultimate goal of these carefully orchestrated actions is purification and cleansing. The application of blood effectively wipes away any ordinary, secular nature that may have clung to the altar. Through this process, the altar is completely purified, enters its required state of holiness, and is made ready to provide atonement for the people moving forward. This mirrors the original preparation process performed with the sin-offering bull during the dedication of the Tabernacle in the days of Moses [רש״י, מצודת דוד, מצודת ציון, ביאור שטיינזלץ].