Birth
What is round, filled with water, and meant to contain an entire human? The womb is the obvious answer. (An eye can figuratively contain, at least view, a whole person.) But the baptismal font also meets this qualification. The womb allows a child to grow in physical symmetry because it is filled with amniotic fluid, which creates an environment free from gravity. Otherwise, a child's skeleton would be compressed by the enclosure of the womb, and emerge deformed. "The waters" figure prominently in the story of earth's creation in Genesis, and the twelve oxen beneath correspond to the twelve tribes of Israel, perhaps symbolizing their creation and scattering in all directions into the world.
The depths of the font might also symbolize the unfathomable depths of the earth's history, creation, and whatever else is lost in the mists of time. We flatter ourselves, creationist and scientist alike, that we know where the earth came from. D&C 101:32-34 seems to indicate otherwise: "Yea, verily I say unto you, in that day when the Lord shall come, he shall reveal all things—Things which have passed, and hidden things which no man knew, things of the earth, by which it was made, and the purpose and the end thereof—Things most precious, things that are above, and things that are beneath, things that are in the earth, and upon the earth, and in heaven."
The Font is the antithesis then of the Altar of Sacrifice; the Altar is male, associated with death and fire, with squared edges and horns, almost cube-shaped, where priests kill offerings and sprinkle blood. The Font is circular, associated with the female womb and birth, or rebirth, and creation.
Just as we were born into an earthly family, we are also symbolically born into Jesus' family, adopted as His sons and daughters. Physical birth included immersion in water, emerging a new person; birth into Jesus' family includes being immersed by one of His authorized representatives and brought up again. This is a sign of humility, trust, and submission, since being dipped backwards in water is a compromising position (when viewed objectively).
Bath
Baptism is for the remission of sins, and the imagery of a bath tub is appropriate here. The worldly grime and dirt must be cleansed, especially before one enters the Temple. This would have been even more necessary after performing the ordinances of sacrifice. Charcoal and the blood of sacrifices would need to be cleaned of before entering the structure of the Temple itself. In the courtyard of the portable Tabernacle in the wilderness, this mammoth structure was originally simply a large bronze basin called the Laver. The Font was big enough to immerse an entire person; the Laver was probably only big enough to stand by and draw water to wash one's limbs. In either case, one was rendered ritually clean by washing in the outer court before entering the presence of the Lord. The twelve tribes escaped the worldly enslavement of Egypt by passing through the Red Sea, where the Egyptian army was drowned. Likewise, we are cleansed from sin in the waters of baptism, and the twelve oxen hark back to that event. The 2000 pigs with the legion of evil spirits ran down the hillside into the sea, and I wonder if the drowning of these unclean animals filled with unclean spirits harked back to the cleansing effects of baptism and the Laver.
Jesus was the Lamb of God, and so the living embodiment of the Aaronic Priesthood, John the Baptist, was responsible for baptizing Him. It is worth noting that only the High Priest was allowed inside the Holy of Holies, while the further you go from that place, the lesser your status as a priest. The Brazen Sea and Altar of Sacrifice are in the outer courtyard, exposed to sun and rain, and the eyes of the people. Aaronic priesthood is then literally preparatory (to enter the Temple) and concerned with outward ordinances (outside the building). Today, Aaronic priesthood bearers still focus on physical, material things—fast offerings, bishop's storehouses, baptism (a public event), preparing the sacrament, etc. We think of "preparatory" as preparing the priesthood bearers themselves for bigger responsibilities, but the ordinances they administer are also preparatory for those who participate in them; they lead to the inner ordinances of the Temple.
Burial
The idea of death, burial, and resurrection is also a legitimate interpretation of the Brazen Sea. When the flood covered the earth during its baptism, Noah and his family boarded the "ark," literally a "coffin." Baptism for the dead is recognized by Paul as legitimate, and he also references bodily resurrection in the same breath (1Cor. 15:29). This ordinance anticipates the resurrection, and stands as a potent reminder of what we are hoping for in return for making and honoring our baptismal covenants.
Microcosm of the Plan of Salvation
Below is a section of a letter I wrote to a friend about the possible symbolic meaning of baptism itself. I believe that the ordinance itself, standing in water, being immersed, and brought back up again, is a miniature version of the path we take by leaving heaven, coming here to earth, and being brought back to heaven. I cannot back up my conclusion with any quote from scripture or living oracles, so feel free to take it for what it's worth, or reject it:
"Where did we begin, before the creation? We were in the presence of God. We enjoyed his light, his love, and our Elder Brother, Jesus Christ, was also there. Our perspective was from the top of a mountain which we had spent countless eons climbing, "receiving our first lessons" and subsequent ones from all-knowing Parents. (Can you imagine living with almighty, all-knowing beings and having less than a college education in philosophy and the sciences? I cannot.)
"Then a plan was presented, and it was so intimidating that one third of us opted not to go with it. What was the threat? Spiritual death—falling from our exalted stations, leaving God's presence and losing our memory of Him behind a veil—and physical death, losing our bodies immediately after we had acquired them. How did we have the courage to face these immense obstacles?
"Rev. 12:11 'And they (we) overcame him (Satan) by the blood of the Lamb, and by the word of their testimony; and they loved not their lives unto the death.'
"We had courage to face the enormous risks of this mortal experience because we trusted Jesus' commitment to be our Savior, our Rescuer. "Here am I; send me." He agreed to get us out of this dark and dreary existence in one piece. Yes, we agreed to descend into the murkiness of life, but in the eternal scheme, it was only a brief blink of an eye: 'Thine adversity and thine affliction shall be but as small moment.'
[I mentioned early in the letter that we must hold on to someone else while we are being baptized, and draw a comparison in the plan of salvation here.]
"The Atonement is the way God holds onto us, binds us to Him. Jesus holds on to us; He is bound to our Father; they will get us out of this, and send the Spirit to guide us as their personal representative. Together they will get us back up to where we started, resurrected, reunited, At-One with our Heavenly Parents again.
"But our participation is also required. God holds onto us, but we must also hold onto Him. How?
"Adam was taught by messengers how to get back to the presence of God: Faith in Jesus Christ (this engenders hope, charity, and general good works); Repentance (stop doing bad, start doing good); Baptism (immersion in water as a sign of covenant to always do the will of God and remember His Son); and the baptism of the Holy Ghost (actively receiving and following Him back into the presence of God). These principles constitute the way in which we reach for and grasp God's redemptive hand. They allow us to access the justifying, sanctifying, purifying power of the Atonement.
"The ordinance of baptism symbolically encapsulates the plan of salvation. We begin in the presence of God, submit to His will and trust Him to get us out of this mess, and hopefully reemerge with rejoicing, and warm embraces with those we previously left before we started a new phase of existence. And there is a spider lurking down here, but we need not fear, if we hold on to God. He will bring us up again...
"In a quiet moment, a group asked Brigham Young, “President Young, why is it that the Lord is not always at our side promoting universal happiness and seeing to it that the needs of people are met, caring especially for His Saints? Why is it so difficult at times?” His response was instructive:
"'Because man is destined to be a God, and he must be able to demonstrate that he is for God and to develop his own resources so that he can act independently and yet humbly.” Then he added, “It is the way it is because we must learn to be righteous in the dark.' (Brigham Young’s Office Journal, 28 January 1857; emphasis added.)
'In this small moment of submersion and darkness, we can still find the Light of the world, and he is with us, holding our hand to bring us back up again."
Clean
Joseph F. Smith tells a story of an important dream he had on his mission:
“I was very
much oppressed [when I was] on a mission. I was almost naked and
entirely friendless, except [for] the friendship of a poor, benighted …
people. I felt as if I was so debased in my condition of poverty, lack
of intelligence and knowledge, just a boy, that I hardly dared look a …
man in the face.
“While
in that condition I dreamed [one night] that I was on a journey, and I
was impressed that I ought to hurry—hurry with all my might, for fear I
might be too late. I rushed on my way as fast as I possibly could, and I
was only conscious of having just a little bundle, a handkerchief with a
small bundle wrapped in it. I did not realize … what it was, when I was
hurrying as fast as I could; but finally I came to a wonderful mansion. … I thought I knew that was my destination. As I passed towards it, as
fast as I could, I saw a notice [which read B-A-T-H], ‘Bath.’ I
turned aside quickly and went into the bath and washed myself clean. I
opened up this little bundle that I had, and there was [some] white,
clean [clothing], a thing I had not seen for a long time, because the
people I was with did not think very much of making things exceedingly
clean. But my [clothing was] clean, and I put [it] on. Then I rushed to
what appeared to be a great opening, or door. I knocked and the door
opened, and the man who stood there was the Prophet Joseph Smith.
He looked at me a little reprovingly, and the first words he said:
‘Joseph, you are late.’ Yet I took confidence and [replied]:
“‘Yes, but I am clean—I am clean!’
“He clasped my hand and drew me in, then closed the great door. I felt his hand just as tangible as I ever felt the hand of man. I knew him, and when I entered I saw my father, and Brigham [Young] and Heber [C. Kimball], and Willard [Richards], and other good men that I had known, standing in a row. I looked as if it were across this valley, and it seemed to be filled with a vast multitude of people, but on the stage were all the people that I had known. My mother was there, and she sat with a child in her lap; and I could name over as many as I remember of their names, who sat there, who seemed to be among the chosen, among the exalted. …
“[When I had this dream,] I was alone on a mat, away up in the mountains of Hawaii—no one was with me. But in this vision I pressed my hand up against the Prophet, and I saw a smile cross his countenance. …
“When I awoke that morning I was a man, although only [still] a boy. There was not anything in the world that I feared [after that]. I could meet any man or woman or child and look them in the face, feeling in my soul that I was a man every whit. That vision, that manifestation and witness that I enjoyed at that time has made me what I am, if I am anything that is good, or clean, or upright before the Lord, if there is anything good in me. That has helped me out in every trial and through every difficulty” (Gospel Doctrine, 5th ed. [1939], 542–43, quoted by Pres. Hinckley, Apr. 2007 Gen. Conf.).
Appearing before God, clean, fresh, and clothed in righteousness, is the ultimate longing of us all, and the Font gives us the chance to arrive at our destination in the proper state, unsullied by the world.