דברי הימים ב, פרק ד׳, פסוק ו׳

The water system established in Solomon's Temple was designed to handle the massive scale of purification and sacrifice preparation. Roles were clearly divided among various vessels to ensure every ritual need was met. Ten new copper basins, shaped like large cauldrons equipped with small faucets, were created for these daily tasks [מצודת ציון, ביאור שטיינזלץ]. They were positioned with five on the right and five on the left. The primary approach among commentators is that these did not replace the original basin crafted by Moses in the wilderness. Instead, they were added to it and placed on either side [רש״י, מצודת דוד, רד״ק]. While there is some discussion regarding whether the priests actually utilized all the new vessels or relied solely on the original one, the conclusion is that they used all of them [רד״ק].

These basins served two main purposes. First, they provided water for the priests to wash their hands and feet before beginning their service, fulfilling the original Commandment [רש״י, מצודת דוד, רלב״ג]. Second, they were used to wash the meat of the burnt offerings, such as the innards and legs, before they were placed on the altar [מצודת ציון]. This rinsing process was strictly reserved for the burnt offerings. Peace offerings did not require this washing at the Temple, as they were taken and eaten by their owners throughout the city [רש״י]. Regarding these dual functions, some interpret that the basins were used exclusively to wash the burnt offerings. However, another approach maintains that they served a shared purpose, functioning both for washing the priests and rinsing the sacrifices [רד״ק].

In contrast to the smaller basins, the massive copper pool known as the "Sea" was designated for the full immersion of the priests. It functioned like a standard ritual bath to purify them from ritual impurity [רש״י, מצודת דוד, רלב״ג, רד״ק, ביאור שטיינזלץ]. Using a man-made vessel for this kind of purification presents a legal challenge, as valid immersion requires natural, undrawn water. To resolve this, an aqueduct was constructed to bring water from the Ein Eitam spring. This water flowed underground directly to the bronze oxen that supported the large pool. Because the legs of these oxen were hollow and pierced, the natural spring water bubbled up through them into the pool, rendering it legally valid for immersion [מצודת דוד, רד״ק]. Another possibility is that the pool had pipes extending from it, allowing the priests to wash directly from its naturally flowing water [ביאור שטיינזלץ].