Molten Sea, Chaos Tamed
It was seemingly inspired by the laver used by the priests ministering in the desert Mishkan to purify their hands and feet (II Chronicles 4:6). I say "seemingly," because the dimensions of the Yam Mutzak were such that, unless there was a mechanism not mentioned in the Biblical accounts, it was too big to be used as a basin for ritual washing. It is reasonable to argue that it was more symbolic than functional - but symbolic of what? The medieval Midrash states it symbolized "the world," but this seems like a somewhat lazy interpretation, and a rather awkward one at that. Kabbalah extracted elaborate meaning from its many features, almost all of them understood to allude to the sefirot. In both cases, the explanations seem like retrojections, the imposition of later ideas and concerns on an earlier phenomenon. What did it mean to the Israelites who built it and maintained it?
The basin has a Ancient Near Eastern parallel, the Apsu pool, a square tank of holy water that was found in the courtyard of Mesopotamian temples. Apsu is the tellurian "sweetwater sea" (the aquifer) that preceded and supports the earth. Mythologically, the Apsu is the home of Enki/Ea and the wellspring of creation. In one version of Mesopotamian mythology, Apsu is personified as the companion of Tiamat, the salt water sea dragon, and is destroyed by Ea. Besides being a purification device, the apsu tank probably conveyed to the entering worshipper that this sanctuary was the residence of divinity. It may be there were rituals specifically associated with the tank.
So perhaps the Sea was meant to symbolize the mythic cosmos in a similar way. So what's the specific Israelite meaning? Let's start with the name. Usually translated as "molten sea" or "cast sea," based on the adjective tzuk, "melted," this translation is reinforced elsewhere in Scriptures when it is referred to as the "bronze sea". Straight forward, but detached from any clear intellectual context. Is it a "sea" to say the world is like the sea? That's a lot of bronze for an odd analogy. Yet the word mutzak could also be derived from the Hebrew noun tzok, meaning "contraint" or "distress." From this we could plausibly call it the "constrained sea," or "bound sea."
This latter translation makes a great deal of sense to me, because one of the great mythic acts of the God of Israel is the taming of chaos, as embodied by water. God sets the boundaries of the water, allowing the land to appear (Gen. 1:9; Ps. 74:13; 104:7-8; Job 38:8-11). The bound waters are emblematic of cosmos triumphing over chaos. Thus the Yam Mutzak visually encapsulates for the Israelite worshipper the drama of divine creation just as he approaches the Temple, the edenic structure with its cherubs, trees, flowers, and the seat of Divine Presence. The Sea, then, was likely part of a mythic narrative told in architecture.
Why the oxen? Bulls, we know, were popular and widely used symbols of divine power. The Israelite northerners thought the bull to be a suitable symbol for the God of Israel despite, or perhaps because of, the whole Golden Calf incident (I Kings 12:28-31). It is a story told, with much contempt, I might add, from a Southern perspective. Yet for the modern reader it's a subtle distinction - are two calves in the sanctuary more abhorrent than twelve oxen just outside? Why are cherubs cool, but bulls out of bounds, as it were? It seems at some point, both groups used cows as a totem for the God of Israel. And at some point, this icon became problematic. And twelve? Twelve tribes of Israel, of course, in which case the oxen symbolize Israel's role in sustaining the cosmos through sacrifices and fidelity to God. Alternately, the twelve oxen could present the twelves houses of the zodiac, the celestial order that surrounds the world.
Zal g'mor - To learn more consult the Encyclopedia of Jewish Myth, Magic, and Mysticism: http://www.amazon.com/Encyclopedia-Jewish-Myth-Magic-Mysticism/dp/0738709050