We find several instances of burnt offerings before Moses was commissioned to structure and systematize the ceremony into a religious activity. The burnt offering was principally employed as sin atonement. We can find a lot of information regarding the purpose of this ritual in other sources.
The interesting part right now is the peculiarity which occurred while constructing the altar, an oddity which was not included in the original recipe Moses received from God (Exod 27:1-8).
“He made the basin of bronze and its stand of bronze, from the mirrors of the ministering women who ministered in the entrance of the tent of meeting.” (Exodus 38:8)
In ancient times mirrors were made from bronze. In this context they symbolize our independence (When we in this context utilizes the word independence we mean the false self-syndrome, that is, the sentiment that we are not containers of either sin or God's Spirit, but independent entities.); the mirrors cast back our own image. We either have a conceited image of ourselves or we find our defects in the mirror. No matter how we behold our image is not a correct reflection of us. Something is lacking, namely our union with Christ.
The false mirrors of man are thus melted and amalgamated into the basin which most likely is a type of God who burnt His only begotten son as a burnt offering for our sins. Christ has become our sin atonement, he is our burnt offering. He is now our true mirror – the only one who reflects a perfect image of our being. The melting into God provides us with a beautiful picture of the union; every atom is rearranged and blended in the melting process until it becomes a perfect mix. When the mixture set it is forever molded together. It is impossible to separate the two, they are forever one.
A mirror also represents introspection, which is considered a necessity in many faith systems to facilitate change of behavior. Most are familiar with introspection as a sure path to condemnation. To ensure that our gaze is upward the mirrors are melted and done away with. It is the upward gaze which enables man to behold the free gift of perfection in Christ.