"And then shall ye immerse them in the water, and come forth again out of the water."
The purpose of baptism is to follow Christ's example. (John 10: 27, John 14: 15.) It symbolizes the death of the old man of sin, and the resurrection into a new life in Christ. (Romans 6: 4.) That symbol cannot be mirrored by sprinkling. It must involve immersion.
In immersion we are placed below the surface of the water, in the same way as the dead are buried below ground.
In immersion the breath of life is cut off while under the water, and restored anew when you "come forth again out of the water."
In the case of the officiator, they are the one who immerses and then brings the recipient up out of the water. Performing this ordinance puts the officiator in the role of the Lord who holds the keys of death (Rev. 1: 18) and resurrection (2 Nephi 2: 8).
Those who are baptized, and those who officiate, enact, by symbol, some eternal truths regarding the plan of salvation. In the very moment the ordinance is performed there is a renewal in symbol of life, innocence, forgiveness and resurrection. The earth itself is blessed by such things as baptism and other ordinances. The earth itself is defiled when the ordinances are not kept exactly as prescribed. (Isa. 24: 5; Moses 7: 28.)
The earth knows that God ordained the ordinances of heaven and earth. (Jeremiah 33: 25.) As regular and reliable as the movements of the sun and moon are, so too should the ordinances of the Lord be kept in their appointed ways. (Jeremiah 31: 35-36.)
The heavens and earth rejoice when the ordinances are kept. They symbolize eternal hope, man's acceptance of God's plan, and a presence of righteousness in a fallen world. Our own participation in ordinances are vital to our own renewal, and the renewal of all creation through redemption of each individual soul.
The baptism ordinance, like all those that follow after, is intended not merely to fulfill an initiation rite. It is intended to communicate light and truth into the mind of the individual who is performing and receiving the ordinance. It is meant to enlighten.
I have discussed previously the meaning of "come forth" used by Christ in restoring life to Lazarus (John 11: 43) and therefore won't repeat it again here. It is no accident the Lord employs the same meaning here as there. We are rising from the tomb of sin which imprisons us into the new life awaiting us in Christ.
The Lord is more than brilliant. He is filled with light and truth. The closer you draw to Him, the more light and truth you begin to receive from Him.